2008-11-03 Tatsuhiro Tsujikawa <tujikawa at rednoah dot com>

	Made BtRegistry non-static object. Now DownloadEngine has a
	reference to its object.
	* src/AbstractBtMessage.cc
	* src/ActivePeerConnectionCommand.cc
	* src/ActivePeerConnectionCommand.h
	* src/BtContextAwareCommand.cc
	* src/BtContextAwareCommand.h
	* src/BtExtendedMessage.cc
	* src/BtExtendedMessage.h
	* src/BtInterestedMessage.cc
	* src/BtInterestedMessage.h
	* src/BtNotInterestedMessage.cc
	* src/BtNotInterestedMessage.h
	* src/BtRegistry.cc
	* src/BtRegistry.h
	* src/BtSeederStateChoke.cc
	* src/BtSetup.cc
	* src/DHTGetPeersCommand.cc
	* src/DHTGetPeersCommand.h
	* src/DHTPeerAnnounceEntry.cc
	* src/DHTPeerAnnounceEntry.h
	* src/DHTPeerAnnounceStorage.cc
	* src/DHTPeerAnnounceStorage.h
	* src/DHTPeerLookupTask.cc
	* src/DHTPeerLookupTask.h
	* src/DHTSetup.cc
	* src/DHTSetup.h
	* src/DHTTaskFactory.h
	* src/DHTTaskFactoryImpl.cc
	* src/DHTTaskFactoryImpl.h
	* src/DefaultBtAnnounce.cc
	* src/DefaultBtInteractive.cc
	* src/DefaultBtInteractive.h
	* src/DefaultBtMessageDispatcher.cc
	* src/DefaultBtMessageDispatcher.h
	* src/DefaultBtMessageFactory.cc
	* src/DefaultBtMessageFactory.h
	* src/DefaultBtMessageReceiver.cc
	* src/DefaultBtProgressInfoFile.cc
	* src/DefaultBtProgressInfoFile.h
	* src/DefaultBtRequestFactory.cc
	* src/DefaultBtRequestFactory.h
	* src/DefaultExtensionMessageFactory.cc
	* src/DefaultExtensionMessageFactory.h
	* src/DefaultPeerStorage.cc
	* src/DefaultPeerStorage.h
	* src/DownloadEngine.cc
	* src/DownloadEngine.h
	* src/InitiatorMSEHandshakeCommand.cc
	* src/InitiatorMSEHandshakeCommand.h
	* src/MSEHandshake.cc
	* src/MSEHandshake.h
	* src/Makefile.am
	* src/Makefile.in
	* src/PeerChokeCommand.cc
	* src/PeerChokeCommand.h
	* src/PeerInitiateConnectionCommand.cc
	* src/PeerInitiateConnectionCommand.h
	* src/PeerInteractionCommand.cc
	* src/PeerInteractionCommand.h
	* src/PeerObject.h
	* src/PeerReceiveHandshakeCommand.cc
	* src/PeerReceiveHandshakeCommand.h
	* src/ReceiverMSEHandshakeCommand.cc
	* src/RequestGroup.cc
	* src/RequestGroup.h
	* src/RequestGroupMan.cc
	* src/RequestGroupMan.h
	* src/SeedCheckCommand.cc
	* src/SeedCheckCommand.h
	* src/ShareRatioSeedCriteria.h
	* src/SimpleBtMessage.cc
	* src/TrackerWatcherCommand.cc
	* src/TrackerWatcherCommand.h
	* src/UTPexExtensionMessage.cc
	* src/UTPexExtensionMessage.h
	* test/BtCancelMessageTest.cc
	* test/BtChokeMessageTest.cc
	* test/BtExtendedMessageTest.cc
	* test/BtInterestedMessageTest.cc
	* test/BtNotInterestedMessageTest.cc
	* test/BtPieceMessageTest.cc
	* test/BtPortMessageTest.cc
	* test/BtRegistryTest.cc
	* test/BtRejectMessageTest.cc
	* test/BtRequestMessageTest.cc
	* test/DHTPeerAnnounceEntryTest.cc
	* test/DHTPeerAnnounceStorageTest.cc
	* test/DefaultBtMessageDispatcherTest.cc
	* test/DefaultBtMessageFactoryTest.cc
	* test/DefaultBtProgressInfoFileTest.cc
	* test/DefaultBtRequestFactoryTest.cc
	* test/DefaultExtensionMessageFactoryTest.cc
	* test/MSEHandshakeTest.cc
	* test/MockDHTTaskFactory.h
	* test/ShareRatioSeedCriteriaTest.cc
	* test/UTPexExtensionMessageTest.cc

74 files changed, 1161 insertions, 837 deletions

diff --git a/src/AbstractBtMessage.cc b/src/AbstractBtMessage.cc
index feb9e770..51777769 100644
--- a/src/AbstractBtMessage.cc
+++ b/src/AbstractBtMessage.cc
@@ -36,7 +36,6 @@
 #include "Peer.h"
 #include "BtContext.h"
 #include "PieceStorage.h"
-#include "BtRegistry.h"
 #include "BtEventListener.h"
 #include "BtMessageValidator.h"
 #include "LogFactory.h"
@@ -99,7 +98,6 @@ SharedHandle<BtMessageValidator> AbstractBtMessage::getBtMessageValidator() cons
 void AbstractBtMessage::setBtContext(const SharedHandle<BtContext>& btContext)
 {
   this->btContext = btContext;
-  this->pieceStorage = PIECE_STORAGE(btContext);
 }
 
 SharedHandle<BtContext> AbstractBtMessage::getBtContext() const
diff --git a/src/ActivePeerConnectionCommand.cc b/src/ActivePeerConnectionCommand.cc
index 36a7416f..1941b2a8 100644
--- a/src/ActivePeerConnectionCommand.cc
+++ b/src/ActivePeerConnectionCommand.cc
@@ -52,19 +52,21 @@
 
 namespace aria2 {
 
-ActivePeerConnectionCommand::ActivePeerConnectionCommand(int cuid,
-							 RequestGroup* requestGroup,
-							 DownloadEngine* e,
-							 const BtContextHandle& btContext,
-							 time_t interval)
-  :Command(cuid),
-   BtContextAwareCommand(btContext),
-   RequestGroupAware(requestGroup),
-   interval(interval),
-   e(e),
-   _thresholdSpeed(e->option->getAsInt(PREF_BT_REQUEST_PEER_SPEED_LIMIT)),
-   _maxUploadSpeedLimit(e->option->getAsInt(PREF_MAX_UPLOAD_LIMIT)),
-   _numNewConnection(5)
+ActivePeerConnectionCommand::ActivePeerConnectionCommand
+(int cuid,
+ RequestGroup* requestGroup,
+ DownloadEngine* e,
+ const BtContextHandle& btContext,
+ time_t interval)
+  :
+  Command(cuid),
+  RequestGroupAware(requestGroup),
+  _btContext(btContext),
+  interval(interval),
+  e(e),
+  _thresholdSpeed(e->option->getAsInt(PREF_BT_REQUEST_PEER_SPEED_LIMIT)),
+  _maxUploadSpeedLimit(e->option->getAsInt(PREF_MAX_UPLOAD_LIMIT)),
+  _numNewConnection(5)
 {
   unsigned int maxDownloadSpeed = e->option->getAsInt(PREF_MAX_DOWNLOAD_LIMIT);
   if(maxDownloadSpeed > 0) {
@@ -75,32 +77,32 @@ ActivePeerConnectionCommand::ActivePeerConnectionCommand(int cuid,
 ActivePeerConnectionCommand::~ActivePeerConnectionCommand() {}
 
 bool ActivePeerConnectionCommand::execute() {
-  if(btRuntime->isHalt()) {
+  if(_btRuntime->isHalt()) {
     return true;
   }
   if(checkPoint.elapsed(interval)) {
     checkPoint.reset();
     TransferStat tstat = _requestGroup->calculateStat();
     if(// for seeder state
-       (pieceStorage->downloadFinished() && btRuntime->lessThanMaxPeers() &&
+       (_pieceStorage->downloadFinished() && _btRuntime->lessThanMaxPeers() &&
 	(_maxUploadSpeedLimit == 0 ||
 	 tstat.getUploadSpeed() < _maxUploadSpeedLimit*0.8)) ||
        // for leecher state
-       (!pieceStorage->downloadFinished() &&
+       (!_pieceStorage->downloadFinished() &&
 	(tstat.getDownloadSpeed() < _thresholdSpeed ||
-	 btRuntime->lessThanMinPeers()))) {
-      unsigned int numConnection = pieceStorage->downloadFinished() ?
+	 _btRuntime->lessThanMinPeers()))) {
+      unsigned int numConnection = _pieceStorage->downloadFinished() ?
 	std::min(_numNewConnection,
-		 BtRuntime::MAX_PEERS-btRuntime->getConnections()) :
+		 BtRuntime::MAX_PEERS-_btRuntime->getConnections()) :
 	_numNewConnection;
       for(unsigned int numAdd = numConnection;
-	  numAdd > 0 && peerStorage->isPeerAvailable(); --numAdd) {
-	PeerHandle peer = peerStorage->getUnusedPeer();
+	  numAdd > 0 && _peerStorage->isPeerAvailable(); --numAdd) {
+	PeerHandle peer = _peerStorage->getUnusedPeer();
 	connectToPeer(peer);
       }
-      if(btRuntime->getConnections() == 0 &&
-	 !pieceStorage->downloadFinished()) {
-	btAnnounce->overrideMinInterval(BtAnnounce::DEFAULT_ANNOUNCE_INTERVAL);
+      if(_btRuntime->getConnections() == 0 &&
+	 !_pieceStorage->downloadFinished()) {
+	_btAnnounce->overrideMinInterval(BtAnnounce::DEFAULT_ANNOUNCE_INTERVAL);
       }
     }
   }
@@ -115,10 +117,37 @@ void ActivePeerConnectionCommand::connectToPeer(const PeerHandle& peer)
   }
   peer->usedBy(CUIDCounterSingletonHolder::instance()->newID());
   PeerInitiateConnectionCommand* command =
-    new PeerInitiateConnectionCommand(peer->usedBy(), _requestGroup, peer, e, btContext);
+    new PeerInitiateConnectionCommand(peer->usedBy(), _requestGroup, peer, e,
+				      _btContext, _btRuntime);
+  command->setPeerStorage(_peerStorage);
+  command->setPieceStorage(_pieceStorage);
   e->commands.push_back(command);
   logger->info(MSG_CONNECTING_TO_PEER,
 	       cuid, peer->ipaddr.c_str());
 }
 
+void ActivePeerConnectionCommand::setBtRuntime
+(const SharedHandle<BtRuntime>& btRuntime)
+{
+  _btRuntime = btRuntime;
+}
+
+void ActivePeerConnectionCommand::setPieceStorage
+(const SharedHandle<PieceStorage>& pieceStorage)
+{
+  _pieceStorage = pieceStorage;
+}
+
+void ActivePeerConnectionCommand::setPeerStorage
+(const SharedHandle<PeerStorage>& peerStorage)
+{
+  _peerStorage = peerStorage;
+}
+
+void ActivePeerConnectionCommand::setBtAnnounce
+(const SharedHandle<BtAnnounce>& btAnnounce)
+{
+  _btAnnounce = btAnnounce;
+}
+
 } // namespace aria2
diff --git a/src/ActivePeerConnectionCommand.h b/src/ActivePeerConnectionCommand.h
index 6204ad76..77b6a6f1 100644
--- a/src/ActivePeerConnectionCommand.h
+++ b/src/ActivePeerConnectionCommand.h
@@ -36,7 +36,7 @@
 #define _D_ACTIVE_PEER_CONNECTION_COMMAND_H_
 
 #include "Command.h"
-#include "BtContextAwareCommand.h"
+#include "SharedHandle.h"
 #include "RequestGroupAware.h"
 #include "TimeA2.h"
 
@@ -44,12 +44,22 @@ namespace aria2 {
 
 class DownloadEngine;
 class Peer;
+class BtContext;
+class BtRuntime;
+class PieceStorage;
+class PeerStorage;
+class BtAnnounce;
 
 class ActivePeerConnectionCommand : public Command,
-				    public BtContextAwareCommand,
 				    public RequestGroupAware
 {
 private:
+  SharedHandle<BtContext> _btContext;
+  SharedHandle<BtRuntime> _btRuntime;
+  SharedHandle<PieceStorage> _pieceStorage;
+  SharedHandle<PeerStorage> _peerStorage;
+  SharedHandle<BtAnnounce> _btAnnounce;
+
   time_t interval; // UNIT: sec
   DownloadEngine* e;
   Time checkPoint;
@@ -73,6 +83,14 @@ public:
   {
     _numNewConnection = numNewConnection;
   }
+
+  void setBtRuntime(const SharedHandle<BtRuntime>& btRuntime);
+
+  void setPieceStorage(const SharedHandle<PieceStorage>& pieceStorage);
+
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
+
+  void setBtAnnounce(const SharedHandle<BtAnnounce>& btAnnounce);
 };
 
 } // namespace aria2
diff --git a/src/BtContextAwareCommand.cc b/src/BtContextAwareCommand.cc
deleted file mode 100644
index 8d88138f..00000000
--- a/src/BtContextAwareCommand.cc
+++ /dev/null
@@ -1,56 +0,0 @@
-/* <!-- copyright */
-/*
- * aria2 - The high speed download utility
- *
- * Copyright (C) 2006 Tatsuhiro Tsujikawa
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
- *
- * In addition, as a special exception, the copyright holders give
- * permission to link the code of portions of this program with the
- * OpenSSL library under certain conditions as described in each
- * individual source file, and distribute linked combinations
- * including the two.
- * You must obey the GNU General Public License in all respects
- * for all of the code used other than OpenSSL.  If you modify
- * file(s) with this exception, you may extend this exception to your
- * version of the file(s), but you are not obligated to do so.  If you
- * do not wish to do so, delete this exception statement from your
- * version.  If you delete this exception statement from all source
- * files in the program, then also delete it here.
- */
-/* copyright --> */
-#include "BtContextAwareCommand.h"
-#include "BtRegistry.h"
-#include "BtContext.h"
-#include "BtRuntime.h"
-#include "PieceStorage.h"
-#include "PeerStorage.h"
-#include "BtAnnounce.h"
-#include "BtProgressInfoFile.h"
-
-namespace aria2 {
-
-BtContextAwareCommand::BtContextAwareCommand(const BtContextHandle& btContext):
-  btContext(btContext),
-  btRuntime(BT_RUNTIME(btContext)),
-  pieceStorage(PIECE_STORAGE(btContext)),
-  peerStorage(PEER_STORAGE(btContext)),
-  btAnnounce(BT_ANNOUNCE(btContext)),
-  btProgressInfoFile(BT_PROGRESS_INFO_FILE(btContext)) {}
-
-BtContextAwareCommand::~BtContextAwareCommand() {}
-
-} // namespace aria2
diff --git a/src/BtContextAwareCommand.h b/src/BtContextAwareCommand.h
deleted file mode 100644
index bdef4f0d..00000000
--- a/src/BtContextAwareCommand.h
+++ /dev/null
@@ -1,67 +0,0 @@
-/* <!-- copyright */
-/*
- * aria2 - The high speed download utility
- *
- * Copyright (C) 2006 Tatsuhiro Tsujikawa
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
- *
- * In addition, as a special exception, the copyright holders give
- * permission to link the code of portions of this program with the
- * OpenSSL library under certain conditions as described in each
- * individual source file, and distribute linked combinations
- * including the two.
- * You must obey the GNU General Public License in all respects
- * for all of the code used other than OpenSSL.  If you modify
- * file(s) with this exception, you may extend this exception to your
- * version of the file(s), but you are not obligated to do so.  If you
- * do not wish to do so, delete this exception statement from your
- * version.  If you delete this exception statement from all source
- * files in the program, then also delete it here.
- */
-/* copyright --> */
-#ifndef _D_BT_CONTEXT_AWARE_COMMAND_H_
-#define _D_BT_CONTEXT_AWARE_COMMAND_H_
-
-#include "common.h"
-#include "SharedHandle.h"
-
-namespace aria2 {
-
-class BtContext;
-class BtRuntime;
-class PieceStorage;
-class PeerStorage;
-class BtAnnounce;
-class BtProgressInfoFile;
-
-class BtContextAwareCommand
-{
-protected:
-  SharedHandle<BtContext> btContext;
-  SharedHandle<BtRuntime> btRuntime;
-  SharedHandle<PieceStorage> pieceStorage;
-  SharedHandle<PeerStorage> peerStorage;
-  SharedHandle<BtAnnounce> btAnnounce;
-  SharedHandle<BtProgressInfoFile> btProgressInfoFile;
-public:
-  BtContextAwareCommand(const SharedHandle<BtContext>& btContext);
-
-  virtual ~BtContextAwareCommand();
-};
-
-} // namespace aria2
-
-#endif // _D_BT_CONTEXT_AWARE_COMMAND_H_
diff --git a/src/BtExtendedMessage.cc b/src/BtExtendedMessage.cc
index b576bd4d..1eac1117 100644
--- a/src/BtExtendedMessage.cc
+++ b/src/BtExtendedMessage.cc
@@ -33,13 +33,6 @@
  */
 /* copyright --> */
 #include "BtExtendedMessage.h"
-#include "BtRegistry.h"
-#include "PeerObject.h"
-#include "BtMessageFactory.h"
-#include "BtMessageReceiver.h"
-#include "BtMessageDispatcher.h"
-#include "BtRequestFactory.h"
-#include "PeerConnection.h"
 #include "ExtensionMessage.h"
 #include "ExtensionMessageFactory.h"
 #include "PeerMessageUtil.h"
@@ -96,7 +89,7 @@ std::string BtExtendedMessage::toString() const {
 }
 
 BtExtendedMessageHandle
-BtExtendedMessage::create(const BtContextHandle& btContext,
+BtExtendedMessage::create(const SharedHandle<ExtensionMessageFactory>& factory,
 			  const PeerHandle& peer,
 			  const unsigned char* data, size_t dataLength)
 {
@@ -109,8 +102,6 @@ BtExtendedMessage::create(const BtContextHandle& btContext,
     throw DlAbortEx
       (StringFormat(EX_INVALID_BT_MESSAGE_ID, id, "extended", ID).str());
   }
-  ExtensionMessageFactoryHandle factory = EXTENSION_MESSAGE_FACTORY(btContext,
-								    peer);
   assert(!factory.isNull());
   ExtensionMessageHandle extmsg = factory->createMessage(data+1,
 							 dataLength-1);
diff --git a/src/BtExtendedMessage.h b/src/BtExtendedMessage.h
index a2b9cc8a..9dfbb8a1 100644
--- a/src/BtExtendedMessage.h
+++ b/src/BtExtendedMessage.h
@@ -39,6 +39,7 @@
 namespace aria2 {
 
 class ExtensionMessage;
+class ExtensionMessageFactory;
 
 class BtExtendedMessage;
 typedef SharedHandle<BtExtendedMessage> BtExtendedMessageHandle;
@@ -59,10 +60,11 @@ public:
 
   static const uint8_t ID = 20;
 
-  static BtExtendedMessageHandle create(const SharedHandle<BtContext>& btContext,
-					const SharedHandle<Peer>& peer,
-					const unsigned char* data,
-					size_t dataLength);
+  static BtExtendedMessageHandle create
+    (const SharedHandle<ExtensionMessageFactory>& factory,
+     const SharedHandle<Peer>& peer,
+     const unsigned char* data,
+     size_t dataLength);
 
   virtual uint8_t getId() { return ID; }
 
diff --git a/src/BtInterestedMessage.cc b/src/BtInterestedMessage.cc
index aab9a612..0e44d9d3 100644
--- a/src/BtInterestedMessage.cc
+++ b/src/BtInterestedMessage.cc
@@ -37,9 +37,7 @@
 #include "DlAbortEx.h"
 #include "message.h"
 #include "Peer.h"
-#include "BtRegistry.h"
 #include "BtContext.h"
-#include "PeerStorage.h"
 #include "StringFormat.h"
 
 namespace aria2 {
@@ -60,9 +58,6 @@ BtInterestedMessageHandle BtInterestedMessage::create(const unsigned char* data,
 
 void BtInterestedMessage::doReceivedAction() {
   peer->peerInterested(true);
-  if(!peer->amChoking()) {
-    PEER_STORAGE(btContext)->executeChoke();
-  }
 }
 
 bool BtInterestedMessage::sendPredicate() const {
diff --git a/src/BtInterestedMessage.h b/src/BtInterestedMessage.h
index 82e03314..9088b259 100644
--- a/src/BtInterestedMessage.h
+++ b/src/BtInterestedMessage.h
@@ -48,6 +48,7 @@ private:
   unsigned char* msg;
 
   static size_t MESSAGE_LENGTH;
+
 public:
   BtInterestedMessage():msg(0) {}
 
diff --git a/src/BtNotInterestedMessage.cc b/src/BtNotInterestedMessage.cc
index f9548e45..8db23d4f 100644
--- a/src/BtNotInterestedMessage.cc
+++ b/src/BtNotInterestedMessage.cc
@@ -37,7 +37,6 @@
 #include "DlAbortEx.h"
 #include "message.h"
 #include "Peer.h"
-#include "BtRegistry.h"
 #include "BtContext.h"
 #include "PeerStorage.h"
 #include "StringFormat.h"
@@ -61,7 +60,7 @@ BtNotInterestedMessageHandle BtNotInterestedMessage::create(const unsigned char*
 void BtNotInterestedMessage::doReceivedAction() {
   peer->peerInterested(false);
   if(!peer->amChoking()) {
-    PEER_STORAGE(btContext)->executeChoke();
+    _peerStorage->executeChoke();
   }
 }
 
@@ -97,4 +96,10 @@ std::string BtNotInterestedMessage::toString() const {
   return NOT_INTERESTED;
 }
 
+void BtNotInterestedMessage::setPeerStorage
+(const SharedHandle<PeerStorage>& peerStorage)
+{
+  _peerStorage = peerStorage;
+}
+
 } // namespace aria2
diff --git a/src/BtNotInterestedMessage.h b/src/BtNotInterestedMessage.h
index 993422f0..ba37c9d6 100644
--- a/src/BtNotInterestedMessage.h
+++ b/src/BtNotInterestedMessage.h
@@ -39,6 +39,7 @@
 
 namespace aria2 {
 
+class PeerStorage;
 class BtNotInterestedMessage;
 
 typedef SharedHandle<BtNotInterestedMessage> BtNotInterestedMessageHandle;
@@ -47,6 +48,8 @@ class BtNotInterestedMessage : public SimpleBtMessage {
 private:
   unsigned char* msg;
   
+  SharedHandle<PeerStorage> _peerStorage;
+
   static size_t MESSAGE_LENGTH;
 public:
   BtNotInterestedMessage():msg(0) {}
@@ -72,6 +75,8 @@ public:
   virtual bool sendPredicate() const;
 
   virtual void onSendComplete();
+
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
 };
 
 } // namespace aria2
diff --git a/src/BtRegistry.cc b/src/BtRegistry.cc
index 1a9b334f..13583dcb 100644
--- a/src/BtRegistry.cc
+++ b/src/BtRegistry.cc
@@ -40,23 +40,10 @@
 #include "BtAnnounce.h"
 #include "BtRuntime.h"
 #include "BtProgressInfoFile.h"
-#include "PeerObject.h"
-#include "BtMessageFactory.h"
-#include "BtRequestFactory.h"
-#include "BtMessageDispatcher.h"
-#include "BtMessageReceiver.h"
-#include "PeerConnection.h"
-#include "ExtensionMessageFactory.h"
 
 namespace aria2 {
 
-BtContextMap BtRegistry::btContextMap;
-PeerStorageMap BtRegistry::peerStorageMap;
-PieceStorageMap BtRegistry::pieceStorageMap;
-BtAnnounceMap BtRegistry::btAnnounceMap;
-BtRuntimeMap BtRegistry::btRuntimeMap;
-BtProgressInfoFileMap BtRegistry::btProgressInfoFileMap;
-PeerObjectClusterRegistry BtRegistry::peerObjectClusterRegistry;
+BtRegistry::BtRegistry() {}
 
 PeerStorageHandle BtRegistry::getPeerStorage(const std::string& key)
 {
@@ -136,25 +123,6 @@ std::deque<SharedHandle<BtContext> > BtRegistry::getAllBtContext()
   return btContextMap.getAll();
 }
 
-PeerObjectClusterHandle
-BtRegistry::getPeerObjectCluster(const std::string& key)
-{
-  return peerObjectClusterRegistry.getHandle(key);
-}
-
-void
-BtRegistry::registerPeerObjectCluster(const std::string& key,
-				      const PeerObjectClusterHandle& cluster)
-{
-  peerObjectClusterRegistry.registerHandle(key, cluster);
-}
-
-void
-BtRegistry::unregisterPeerObjectCluster(const std::string& key)
-{
-  peerObjectClusterRegistry.unregisterHandle(key);
-}
-
 void BtRegistry::unregisterAll() {
   btContextMap.clear();
   peerStorageMap.clear();
@@ -162,7 +130,6 @@ void BtRegistry::unregisterAll() {
   btAnnounceMap.clear();
   btRuntimeMap.clear();
   btProgressInfoFileMap.clear();
-  peerObjectClusterRegistry.clear();
 }
 
 void BtRegistry::unregister(const std::string& key)
@@ -173,7 +140,6 @@ void BtRegistry::unregister(const std::string& key)
   btAnnounceMap.unregisterHandle(key);
   btRuntimeMap.unregisterHandle(key);
   btProgressInfoFileMap.unregisterHandle(key);
-  peerObjectClusterRegistry.unregisterHandle(key);
 }
 
 } // namespace aria2
diff --git a/src/BtRegistry.h b/src/BtRegistry.h
index 2ef55d47..c5f83089 100644
--- a/src/BtRegistry.h
+++ b/src/BtRegistry.h
@@ -36,11 +36,13 @@
 #define _D_BT_REGISTRY_H_
 
 #include "common.h"
-#include "SharedHandle.h"
-#include "HandleRegistry.h"
+
 #include <string>
 #include <map>
 
+#include "SharedHandle.h"
+#include "HandleRegistry.h"
+
 namespace aria2 {
 
 class PeerStorage;
@@ -49,7 +51,6 @@ class BtAnnounce;
 class BtRuntime;
 class BtProgressInfoFile;
 class BtContext;
-class PeerObject;
 
 typedef HandleRegistry<std::string, PeerStorage> PeerStorageMap;
 typedef HandleRegistry<std::string, PieceStorage> PieceStorageMap;
@@ -58,104 +59,49 @@ typedef HandleRegistry<std::string, BtRuntime> BtRuntimeMap;
 typedef HandleRegistry<std::string, BtProgressInfoFile> BtProgressInfoFileMap;
 typedef HandleRegistry<std::string, BtContext>  BtContextMap;
 
-// for BtMessageFactory
-typedef HandleRegistry<std::string, PeerObject> PeerObjectCluster;
-typedef SharedHandle<PeerObjectCluster> PeerObjectClusterHandle;
-typedef HandleRegistry<std::string, PeerObjectCluster> PeerObjectClusterRegistry;
-
 class BtRegistry {
 private:
-  BtRegistry() {}
-
-  static BtContextMap btContextMap;
-  static PeerStorageMap peerStorageMap;
-  static PieceStorageMap pieceStorageMap;
-  static BtAnnounceMap btAnnounceMap;
-  static BtRuntimeMap btRuntimeMap;
-  static BtProgressInfoFileMap btProgressInfoFileMap;
-  static PeerObjectClusterRegistry peerObjectClusterRegistry;
+  BtContextMap btContextMap;
+  PeerStorageMap peerStorageMap;
+  PieceStorageMap pieceStorageMap;
+  BtAnnounceMap btAnnounceMap;
+  BtRuntimeMap btRuntimeMap;
+  BtProgressInfoFileMap btProgressInfoFileMap;
 public:
-  static SharedHandle<BtContext> getBtContext(const std::string& key);
-  static void registerBtContext(const std::string& key,
-				const SharedHandle<BtContext>& btContext);
-
-  static SharedHandle<PeerStorage> getPeerStorage(const std::string& key);
-  static void registerPeerStorage(const std::string& key,
-				  const SharedHandle<PeerStorage>& peer);
+  BtRegistry();
+  
+  SharedHandle<BtContext> getBtContext(const std::string& key);
+  void registerBtContext(const std::string& key,
+			 const SharedHandle<BtContext>& btContext);
+
+  SharedHandle<PeerStorage> getPeerStorage(const std::string& key);
+  void registerPeerStorage(const std::string& key,
+			   const SharedHandle<PeerStorage>& peer);
 				  
-  static SharedHandle<PieceStorage> getPieceStorage(const std::string& key);
-  static void registerPieceStorage(const std::string& key,
-				   const SharedHandle<PieceStorage>& pieceStorage);
+  SharedHandle<PieceStorage> getPieceStorage(const std::string& key);
+  void registerPieceStorage(const std::string& key,
+			    const SharedHandle<PieceStorage>& pieceStorage);
 
-  static SharedHandle<BtRuntime> getBtRuntime(const std::string& key);
-  static void registerBtRuntime(const std::string& key,
-				const SharedHandle<BtRuntime>& btRuntime);
+  SharedHandle<BtRuntime> getBtRuntime(const std::string& key);
+  void registerBtRuntime(const std::string& key,
+			 const SharedHandle<BtRuntime>& btRuntime);
 
-  static SharedHandle<BtAnnounce> getBtAnnounce(const std::string& key);
-  static void registerBtAnnounce(const std::string& key,
+  SharedHandle<BtAnnounce> getBtAnnounce(const std::string& key);
+  void registerBtAnnounce(const std::string& key,
 				 const SharedHandle<BtAnnounce>& btAnnounce);
 
-  static SharedHandle<BtProgressInfoFile> getBtProgressInfoFile(const std::string& key);
-  static void registerBtProgressInfoFile(const std::string& key,
-					 const SharedHandle<BtProgressInfoFile>& btProgressInfoFile);
-
-  static std::deque<SharedHandle<BtContext> > getAllBtContext();
+  SharedHandle<BtProgressInfoFile>
+  getBtProgressInfoFile(const std::string& key);
+  void registerBtProgressInfoFile(const std::string& key,
+				  const SharedHandle<BtProgressInfoFile>& file);
 
-  // for PeerObject
-  static PeerObjectClusterHandle
-  getPeerObjectCluster(const std::string& key);
+  std::deque<SharedHandle<BtContext> > getAllBtContext();
 
-  static void
-  registerPeerObjectCluster(const std::string& key,
-			    const PeerObjectClusterHandle& cluster);
+  void unregisterAll();
 
-  static void
-  unregisterPeerObjectCluster(const std::string& key);
-
-  static void unregisterAll();
-
-  static void unregister(const std::string& key);
+  void unregister(const std::string& key);
 };
 
-#define PEER_STORAGE(btContext) \
-BtRegistry::getPeerStorage(btContext->getInfoHashAsString())
-
-#define PIECE_STORAGE(btContext) \
-BtRegistry::getPieceStorage(btContext->getInfoHashAsString())
-
-#define BT_ANNOUNCE(btContext) \
-BtRegistry::getBtAnnounce(btContext->getInfoHashAsString())
-
-#define BT_RUNTIME(btContext) \
-BtRegistry::getBtRuntime(btContext->getInfoHashAsString())
-
-#define BT_PROGRESS_INFO_FILE(btContext) \
-BtRegistry::getBtProgressInfoFile(btContext->getInfoHashAsString())
-
-#define PEER_OBJECT_CLUSTER(btContext) \
-BtRegistry::getPeerObjectCluster(btContext->getInfoHashAsString())
-
-#define PEER_OBJECT(btContext, peer) \
-PEER_OBJECT_CLUSTER(btContext)->getHandle(peer->getID())
-
-#define BT_MESSAGE_DISPATCHER(btContext, peer) \
-PEER_OBJECT(btContext, peer)->btMessageDispatcher
-
-#define BT_MESSAGE_RECEIVER(btContext, peer) \
-PEER_OBJECT(btContext, peer)->btMessageReceiver
-
-#define BT_MESSAGE_FACTORY(btContext, peer) \
-PEER_OBJECT(btContext, peer)->btMessageFactory
-
-#define BT_REQUEST_FACTORY(btContext, peer) \
-PEER_OBJECT(btContext, peer)->btRequestFactory
-
-#define PEER_CONNECTION(btContext, peer) \
-PEER_OBJECT(btContext, peer)->peerConnection
-
-#define EXTENSION_MESSAGE_FACTORY(btContext, peer) \
-PEER_OBJECT(btContext, peer)->extensionMessageFactory
-
 } // namespace aria2
 
 #endif // _D_BT_REGISTRY_H_
diff --git a/src/BtSeederStateChoke.cc b/src/BtSeederStateChoke.cc
index 3e45d344..cabc65e6 100644
--- a/src/BtSeederStateChoke.cc
+++ b/src/BtSeederStateChoke.cc
@@ -33,10 +33,11 @@
  */
 /* copyright --> */
 #include "BtSeederStateChoke.h"
+
+#include <algorithm>
+
 #include "BtContext.h"
 #include "Peer.h"
-#include "BtRegistry.h"
-#include "PeerObject.h"
 #include "BtMessageDispatcher.h"
 #include "BtMessageFactory.h"
 #include "BtRequestFactory.h"
@@ -46,7 +47,6 @@
 #include "Logger.h"
 #include "LogFactory.h"
 #include "a2time.h"
-#include <algorithm>
 
 namespace aria2 {
 
@@ -70,19 +70,19 @@ public:
 
   bool operator()(Peer* left, Peer* right) const
   {
-    size_t leftUpload = BT_MESSAGE_DISPATCHER(_btContext, left)->countOutstandingRequest();
-    size_t rightUpload = BT_MESSAGE_DISPATCHER(_btContext, right)->countOutstandingRequest();
-    if(leftUpload && !rightUpload) {
-      return true;
-    } else if(!leftUpload && rightUpload) {
-      return false;
-    }
+    // TODO Should peer have the reference to message dispatcher?
+//     size_t leftUpload = BT_MESSAGE_DISPATCHER(_btContext, left)->countOutstandingUpload();
+//     size_t rightUpload = BT_MESSAGE_DISPATCHER(_btContext, right)->countOutstandingUpload();
+//     if(leftUpload && !rightUpload) {
+//       return true;
+//     } else if(!leftUpload && rightUpload) {
+//       return false;
+//     }
     const int TIME_FRAME = 20;
     if(!left->getLastAmUnchoking().elapsed(TIME_FRAME) &&
        left->getLastAmUnchoking().isNewer(right->getLastAmUnchoking())) {
       return true;
-    } else if(!right->getLastAmUnchoking().elapsed(TIME_FRAME) &&
-	      right->getLastAmUnchoking().isNewer(left->getLastAmUnchoking())) {
+    } else if(!right->getLastAmUnchoking().elapsed(TIME_FRAME)) {
       return false;
     } else {
       return left->calculateUploadSpeed(_now) > right->calculateUploadSpeed(_now);
diff --git a/src/BtSetup.cc b/src/BtSetup.cc
index eeb8be9b..f7cf3e78 100644
--- a/src/BtSetup.cc
+++ b/src/BtSetup.cc
@@ -56,6 +56,8 @@
 #include "DHTPeerAnnounceStorage.h"
 #include "DHTSetup.h"
 #include "DHTRegistry.h"
+#include "BtProgressInfoFile.h"
+#include "BtAnnounce.h"
 
 namespace aria2 {
 
@@ -70,26 +72,64 @@ void BtSetup::setup(std::deque<Command*>& commands,
   if(btContext.isNull()) {
     return;
   }
+  SharedHandle<BtRegistry> btRegistry = e->getBtRegistry();
+  SharedHandle<PieceStorage> pieceStorage =
+    btRegistry->getPieceStorage(btContext->getInfoHashAsString());
+  SharedHandle<PeerStorage> peerStorage =
+    btRegistry->getPeerStorage(btContext->getInfoHashAsString());
+  SharedHandle<BtRuntime> btRuntime =
+    btRegistry->getBtRuntime(btContext->getInfoHashAsString());
+  SharedHandle<BtAnnounce> btAnnounce =
+    btRegistry->getBtAnnounce(btContext->getInfoHashAsString());
+
   // commands
-  commands.push_back(new TrackerWatcherCommand(CUIDCounterSingletonHolder::instance()->newID(),
-					       requestGroup,
-					       e,
-					       btContext));
-  commands.push_back(new PeerChokeCommand(CUIDCounterSingletonHolder::instance()->newID(),
-					  e,
-					  btContext));
+  {
+    TrackerWatcherCommand* c =
+      new TrackerWatcherCommand(CUIDCounterSingletonHolder::instance()->newID(),
+				requestGroup,
+				e,
+				btContext);
+    c->setPeerStorage(peerStorage);
+    c->setPieceStorage(pieceStorage);
+    c->setBtRuntime(btRuntime);
+    c->setBtAnnounce(btAnnounce);
+    
+    commands.push_back(c);
+  }
+  {
+    PeerChokeCommand* c =
+      new PeerChokeCommand(CUIDCounterSingletonHolder::instance()->newID(),
+			   e,
+			   btContext);
+    c->setPeerStorage(peerStorage);
+    c->setBtRuntime(btRuntime);
 
-  commands.push_back(new ActivePeerConnectionCommand(CUIDCounterSingletonHolder::instance()->newID(),
-						     requestGroup, e, btContext, 10));
+    commands.push_back(c);
+  }
+  {
+    ActivePeerConnectionCommand* c =
+      new ActivePeerConnectionCommand(CUIDCounterSingletonHolder::instance()->newID(),
+				      requestGroup, e, btContext, 10);
+    c->setBtRuntime(btRuntime);
+    c->setPieceStorage(pieceStorage);
+    c->setPeerStorage(peerStorage);
+    c->setBtAnnounce(btAnnounce);
+	    
+    commands.push_back(c);
+  }
 
   if(!btContext->isPrivate() && DHTSetup::initialized()) {
-    DHTRegistry::_peerAnnounceStorage->addPeerAnnounce(btContext);
-    DHTGetPeersCommand* command = new DHTGetPeersCommand(CUIDCounterSingletonHolder::instance()->newID(),
-							 requestGroup,
-							 e,
-							 btContext);
+    DHTRegistry::_peerAnnounceStorage->addPeerAnnounce(btContext->getInfoHash(),
+						       peerStorage);
+    DHTGetPeersCommand* command =
+      new DHTGetPeersCommand(CUIDCounterSingletonHolder::instance()->newID(),
+			     requestGroup,
+			     e,
+			     btContext);
     command->setTaskQueue(DHTRegistry::_taskQueue);
     command->setTaskFactory(DHTRegistry::_taskFactory);
+    command->setBtRuntime(btRuntime);
+    command->setPeerStorage(peerStorage);
     commands.push_back(command);
   }
   SharedHandle<UnionSeedCriteria> unionCri(new UnionSeedCriteria());
@@ -100,16 +140,26 @@ void BtSetup::setup(std::deque<Command*>& commands,
   {
     double ratio = option->getAsDouble(PREF_SEED_RATIO);
     if(ratio > 0.0) {
-      SharedHandle<SeedCriteria> cri(new ShareRatioSeedCriteria(option->getAsDouble(PREF_SEED_RATIO), btContext));
+      SharedHandle<ShareRatioSeedCriteria> cri
+	(new ShareRatioSeedCriteria(option->getAsDouble(PREF_SEED_RATIO),
+				    btContext));
+      cri->setPieceStorage(pieceStorage);
+      cri->setPeerStorage(peerStorage);
+      cri->setBtRuntime(btRuntime);
+
       unionCri->addSeedCriteria(cri);
     }
   }
   if(unionCri->getSeedCriterion().size() > 0) {
-    commands.push_back(new SeedCheckCommand(CUIDCounterSingletonHolder::instance()->newID(),
-					    requestGroup,
-					    e,
-					    btContext,
-					    unionCri));
+    SeedCheckCommand* c =
+      new SeedCheckCommand(CUIDCounterSingletonHolder::instance()->newID(),
+			   requestGroup,
+			   e,
+			   btContext,
+			   unionCri);
+    c->setPieceStorage(pieceStorage);
+    c->setBtRuntime(btRuntime);
+    commands.push_back(c);
   }
 
   if(PeerListenCommand::getNumInstance() == 0) {
@@ -117,7 +167,7 @@ void BtSetup::setup(std::deque<Command*>& commands,
     IntSequence seq = Util::parseIntRange(option->get(PREF_LISTEN_PORT));
     uint16_t port;
     if(listenCommand->bindPort(port, seq)) {
-      BT_RUNTIME(btContext)->setListenPort(port);
+      btRuntime->setListenPort(port);
       commands.push_back(listenCommand);
     } else {
       _logger->error(_("Errors occurred while binding port.\n"));
@@ -125,7 +175,7 @@ void BtSetup::setup(std::deque<Command*>& commands,
     }
   }
 
-  BT_RUNTIME(btContext)->setReady(true);
+  btRuntime->setReady(true);
 }
 
 } // namespace aria2
diff --git a/src/DHTGetPeersCommand.cc b/src/DHTGetPeersCommand.cc
index 498befb8..7981e1c9 100644
--- a/src/DHTGetPeersCommand.cc
+++ b/src/DHTGetPeersCommand.cc
@@ -54,8 +54,8 @@ DHTGetPeersCommand::DHTGetPeersCommand(int32_t cuid,
 				       DownloadEngine* e,
 				       const BtContextHandle& ctx):
   Command(cuid),
-  BtContextAwareCommand(ctx),
   RequestGroupAware(requestGroup),
+  _btContext(ctx),
   _e(e),
   _numRetry(0),
   _lastGetPeerTime(0)
@@ -65,19 +65,21 @@ DHTGetPeersCommand::~DHTGetPeersCommand() {}
 
 bool DHTGetPeersCommand::execute()
 {
-  if(btRuntime->isHalt()) {
+  if(_btRuntime->isHalt()) {
     return true;
   }
   if(_task.isNull() &&
      ((_numRetry > 0 && _lastGetPeerTime.elapsed(RETRY_INTERVAL)) ||
       _lastGetPeerTime.elapsed(GET_PEER_INTERVAL))) {
     logger->debug("Issuing PeerLookup for infoHash=%s",
-		  btContext->getInfoHashAsString().c_str());
-    _task = dynamic_pointer_cast<DHTPeerLookupTask>(_taskFactory->createPeerLookupTask(btContext));
+		  _btContext->getInfoHashAsString().c_str());
+    _task = dynamic_pointer_cast<DHTPeerLookupTask>
+      (_taskFactory->createPeerLookupTask(_btContext, _btRuntime,
+					  _peerStorage));
     _taskQueue->addPeriodicTask2(_task);
   } else if(!_task.isNull() && _task->finished()) {
     _lastGetPeerTime.reset();
-    if(_numRetry < MAX_RETRIES && btRuntime->lessThanMinPeers()) {
+    if(_numRetry < MAX_RETRIES && _btRuntime->lessThanMinPeers()) {
       ++_numRetry;
     } else {
       _numRetry = 0;
@@ -99,4 +101,14 @@ void DHTGetPeersCommand::setTaskFactory(const SharedHandle<DHTTaskFactory>& task
   _taskFactory = taskFactory;
 }
 
+void DHTGetPeersCommand::setBtRuntime(const SharedHandle<BtRuntime>& btRuntime)
+{
+  _btRuntime = btRuntime;
+}
+
+void DHTGetPeersCommand::setPeerStorage(const SharedHandle<PeerStorage>& ps)
+{
+  _peerStorage = ps;
+}
+
 } // namespace aria2
diff --git a/src/DHTGetPeersCommand.h b/src/DHTGetPeersCommand.h
index 8ff5be6d..fc44f48d 100644
--- a/src/DHTGetPeersCommand.h
+++ b/src/DHTGetPeersCommand.h
@@ -36,8 +36,8 @@
 #define _D_DHT_GET_PEERS_COMMAND_H_
 
 #include "Command.h"
-#include "BtContextAwareCommand.h"
 #include "RequestGroupAware.h"
+#include "SharedHandle.h"
 #include "TimeA2.h"
 
 namespace aria2 {
@@ -47,9 +47,11 @@ class DHTTaskFactory;
 class DHTPeerLookupTask;
 class DownloadEngine;
 class RequestGroup;
+class BtContext;
+class BtRuntime;
+class PeerStorage;
 
 class DHTGetPeersCommand:public Command,
-			 public BtContextAwareCommand,
 			 public RequestGroupAware
 {
 private:
@@ -59,6 +61,12 @@ private:
 
   static const size_t MAX_RETRIES = 10;
 
+  SharedHandle<BtContext> _btContext;
+
+  SharedHandle<BtRuntime> _btRuntime;
+
+  SharedHandle<PeerStorage> _peerStorage;
+
   DownloadEngine* _e;
 
   SharedHandle<DHTTaskQueue> _taskQueue;
@@ -82,6 +90,10 @@ public:
   void setTaskQueue(const SharedHandle<DHTTaskQueue>& taskQueue);
 
   void setTaskFactory(const SharedHandle<DHTTaskFactory>& taskFactory);
+
+  void setBtRuntime(const SharedHandle<BtRuntime>& btRuntime);
+
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
 };
 
 } // namespace aria2
diff --git a/src/DHTPeerAnnounceEntry.cc b/src/DHTPeerAnnounceEntry.cc
index 7986b02a..4a092f4c 100644
--- a/src/DHTPeerAnnounceEntry.cc
+++ b/src/DHTPeerAnnounceEntry.cc
@@ -33,13 +33,13 @@
  */
 /* copyright --> */
 #include "DHTPeerAnnounceEntry.h"
-#include "BtContext.h"
-#include "Peer.h"
-#include "BtRegistry.h"
-#include "PeerStorage.h"
+
 #include <cstring>
 #include <algorithm>
 
+#include "Peer.h"
+#include "PeerStorage.h"
+
 namespace aria2 {
 
 DHTPeerAnnounceEntry::DHTPeerAnnounceEntry(const unsigned char* infoHash)
@@ -60,9 +60,15 @@ void DHTPeerAnnounceEntry::addPeerAddrEntry(const PeerAddrEntry& entry)
   notifyUpdate();
 }
 
-void DHTPeerAnnounceEntry::setBtContext(const SharedHandle<BtContext>& btCtx)
+void DHTPeerAnnounceEntry::clearLocal()
 {
-  _btCtx = btCtx;
+  _peerStorage.reset();
+}
+
+void DHTPeerAnnounceEntry::setPeerStorage
+(const SharedHandle<PeerStorage>& peerStorage)
+{
+  _peerStorage = peerStorage;
 }
 
 size_t DHTPeerAnnounceEntry::countPeerAddrEntry() const
@@ -99,7 +105,7 @@ void DHTPeerAnnounceEntry::removeStalePeerAddrEntry(time_t timeout)
 
 bool DHTPeerAnnounceEntry::empty() const
 {
-  return _peerAddrEntries.empty() && _btCtx.isNull();
+  return _peerAddrEntries.empty() && _peerStorage.isNull();
 }
 
 void DHTPeerAnnounceEntry::getPeers(std::deque<SharedHandle<Peer> >& peers) const
@@ -109,11 +115,8 @@ void DHTPeerAnnounceEntry::getPeers(std::deque<SharedHandle<Peer> >& peers) cons
     SharedHandle<Peer> peer(new Peer((*i).getIPAddress(), (*i).getPort()));
     peers.push_back(peer);
   }
-  if(!_btCtx.isNull()) {
-    SharedHandle<PeerStorage> peerStorage = PEER_STORAGE(_btCtx);
-    if(!peerStorage.isNull()) {
-      peerStorage->getActivePeers(peers);
-    }
+  if(!_peerStorage.isNull()) {
+    _peerStorage->getActivePeers(peers);
   }
 }
 
diff --git a/src/DHTPeerAnnounceEntry.h b/src/DHTPeerAnnounceEntry.h
index c91fdef2..f40f1555 100644
--- a/src/DHTPeerAnnounceEntry.h
+++ b/src/DHTPeerAnnounceEntry.h
@@ -36,16 +36,18 @@
 #define _D_DHT_PEER_ANNOUNCE_ENTRY_H_
 
 #include "common.h"
+
+#include <deque>
+
 #include "SharedHandle.h"
 #include "DHTConstants.h"
 #include "PeerAddrEntry.h"
 #include "TimeA2.h"
-#include <deque>
 
 namespace aria2 {
 
 class Peer;
-class BtContext;
+class PeerStorage;
 
 class DHTPeerAnnounceEntry {
 private:
@@ -53,7 +55,7 @@ private:
 
   std::deque<PeerAddrEntry> _peerAddrEntries;
 
-  SharedHandle<BtContext> _btCtx;
+  SharedHandle<PeerStorage> _peerStorage;
 
   Time _lastUpdated;
 public:
@@ -65,7 +67,9 @@ public:
   // if it already exists, update "Last Updated" property.
   void addPeerAddrEntry(const PeerAddrEntry& entry);
 
-  void setBtContext(const SharedHandle<BtContext>& btCtx);
+  void clearLocal();
+
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
 
   size_t countPeerAddrEntry() const;
 
diff --git a/src/DHTPeerAnnounceStorage.cc b/src/DHTPeerAnnounceStorage.cc
index 18162b54..f2e54dd1 100644
--- a/src/DHTPeerAnnounceStorage.cc
+++ b/src/DHTPeerAnnounceStorage.cc
@@ -33,9 +33,13 @@
  */
 /* copyright --> */
 #include "DHTPeerAnnounceStorage.h"
+
+#include <cstring>
+#include <algorithm>
+
 #include "DHTPeerAnnounceEntry.h"
 #include "Peer.h"
-#include "BtContext.h"
+#include "PeerStorage.h"
 #include "DHTConstants.h"
 #include "DHTTaskQueue.h"
 #include "DHTTaskFactory.h"
@@ -44,8 +48,6 @@
 #include "Logger.h"
 #include "Util.h"
 #include "a2functional.h"
-#include <cstring>
-#include <algorithm>
 
 namespace aria2 {
 
@@ -91,24 +93,27 @@ DHTPeerAnnounceStorage::addPeerAnnounce(const unsigned char* infoHash,
 }
 
 // add peer announce as localhost downloading the content
-void DHTPeerAnnounceStorage::addPeerAnnounce(const BtContextHandle& ctx)
+void DHTPeerAnnounceStorage::addPeerAnnounce
+(const unsigned char* infoHash, const SharedHandle<PeerStorage>& peerStorage)
 {
   _logger->debug("Adding localhost to peer announce list: infoHash=%s",
-		 ctx->getInfoHashAsString().c_str());
-  getPeerAnnounceEntry(ctx->getInfoHash())->setBtContext(ctx);
+		 Util::toHex(infoHash, DHT_ID_LENGTH).c_str());
+  SharedHandle<DHTPeerAnnounceEntry> entry =
+    getPeerAnnounceEntry(infoHash);
+  entry->setPeerStorage(peerStorage);
 }
 
-void DHTPeerAnnounceStorage::removePeerAnnounce(const BtContextHandle& ctx)
+void DHTPeerAnnounceStorage::removeLocalPeerAnnounce
+(const unsigned char* infoHash)
 {
-  SharedHandle<DHTPeerAnnounceEntry> entry(new DHTPeerAnnounceEntry(
-					   ctx->getInfoHash()));
+  SharedHandle<DHTPeerAnnounceEntry> entry(new DHTPeerAnnounceEntry(infoHash));
 
   std::deque<SharedHandle<DHTPeerAnnounceEntry> >::iterator i = 
     std::lower_bound(_entries.begin(), _entries.end(), entry, InfoHashLess());
 
   if(i != _entries.end() &&
-     memcmp(ctx->getInfoHash(), (*i)->getInfoHash(), DHT_ID_LENGTH) == 0) {
-    (*i)->setBtContext(SharedHandle<BtContext>());
+     memcmp(infoHash, (*i)->getInfoHash(), DHT_ID_LENGTH) == 0) {
+    (*i)->clearLocal();
     if((*i)->empty()) {
       _entries.erase(i);
     }
diff --git a/src/DHTPeerAnnounceStorage.h b/src/DHTPeerAnnounceStorage.h
index d62d612a..0d9ce87c 100644
--- a/src/DHTPeerAnnounceStorage.h
+++ b/src/DHTPeerAnnounceStorage.h
@@ -41,7 +41,7 @@
 
 namespace aria2 {
 
-class BtContext;
+class PeerStorage;
 class Peer;
 class DHTPeerAnnounceEntry;
 class DHTTaskQueue;
@@ -68,11 +68,12 @@ public:
 		       const std::string& ipaddr, uint16_t port);
 
   // add peer announce as localhost downloading the content
-  void addPeerAnnounce(const SharedHandle<BtContext>& ctx);
+  void addPeerAnnounce(const unsigned char* infoHash,
+		       const SharedHandle<PeerStorage>& peerStorage);
   
-  // give 0 to DHTPeerAnnounceEntry::setBtContext().
+  // Call DHTPeerAnnounceEntry::clearLocal() for infoHash if found.
   // If DHTPeerAnnounceEntry is empty, it is erased.
-  void removePeerAnnounce(const SharedHandle<BtContext>& ctx);
+  void removeLocalPeerAnnounce(const unsigned char* infoHash);
 
   bool contains(const unsigned char* infoHash) const;
 
diff --git a/src/DHTPeerLookupTask.cc b/src/DHTPeerLookupTask.cc
index a2fe6836..392d4a1d 100644
--- a/src/DHTPeerLookupTask.cc
+++ b/src/DHTPeerLookupTask.cc
@@ -41,7 +41,6 @@
 #include "DHTNodeLookupEntry.h"
 #include "DHTMessageDispatcher.h"
 #include "DHTMessageCallback.h"
-#include "BtRegistry.h"
 #include "PeerStorage.h"
 #include "BtRuntime.h"
 #include "BtContext.h"
@@ -52,9 +51,7 @@ namespace aria2 {
 
 DHTPeerLookupTask::DHTPeerLookupTask(const SharedHandle<BtContext>& btContext):
   DHTAbstractNodeLookupTask(btContext->getInfoHash()),
-  _ctx(btContext),
-  _peerStorage(PEER_STORAGE(btContext)),
-  _btRuntime(BT_RUNTIME(btContext)) {}
+  _ctx(btContext) {}
 
 void
 DHTPeerLookupTask::getNodesFromMessage(std::deque<SharedHandle<DHTNode> >& nodes,
@@ -110,4 +107,14 @@ const std::deque<SharedHandle<Peer> >& DHTPeerLookupTask::getPeers() const
   return _peers;
 }
 
+void DHTPeerLookupTask::setBtRuntime(const SharedHandle<BtRuntime>& btRuntime)
+{
+  _btRuntime = btRuntime;
+}
+
+void DHTPeerLookupTask::setPeerStorage(const SharedHandle<PeerStorage>& ps)
+{
+  _peerStorage = ps;
+}
+
 } // namespace aria2
diff --git a/src/DHTPeerLookupTask.h b/src/DHTPeerLookupTask.h
index 3a9cf2e2..b01df29c 100644
--- a/src/DHTPeerLookupTask.h
+++ b/src/DHTPeerLookupTask.h
@@ -69,6 +69,10 @@ public:
   virtual void onFinish();
   
   const std::deque<SharedHandle<Peer> >& getPeers() const;
+
+  void setBtRuntime(const SharedHandle<BtRuntime>& btRuntime);
+
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
 };
 
 } // namespace aria2
diff --git a/src/DHTSetup.cc b/src/DHTSetup.cc
index cead3e80..4dc6faca 100644
--- a/src/DHTSetup.cc
+++ b/src/DHTSetup.cc
@@ -33,6 +33,10 @@
  */
 /* copyright --> */
 #include "DHTSetup.h"
+
+#include <fstream>
+#include <algorithm>
+
 #include "LogFactory.h"
 #include "Logger.h"
 #include "Util.h"
@@ -66,12 +70,11 @@
 #include "DlAbortEx.h"
 #include "RecoverableException.h"
 #include "a2functional.h"
-#include <fstream>
-#include <algorithm>
 
 namespace aria2 {
 
-size_t DHTSetup::_initialized = 0;
+// TODO DownloadEngine should hold this flag.
+bool DHTSetup::_initialized = false;
 
 DHTSetup::DHTSetup():_logger(LogFactory::getInstance()) {}
 
diff --git a/src/DHTSetup.h b/src/DHTSetup.h
index 29339ca1..6cf9376b 100644
--- a/src/DHTSetup.h
+++ b/src/DHTSetup.h
@@ -46,7 +46,7 @@ class Command;
 
 class DHTSetup {
 private:
-  static size_t _initialized;
+  static bool _initialized;
 
   Logger* _logger;
 
diff --git a/src/DHTTaskFactory.h b/src/DHTTaskFactory.h
index c0149729..b5c8dcf9 100644
--- a/src/DHTTaskFactory.h
+++ b/src/DHTTaskFactory.h
@@ -41,6 +41,8 @@
 namespace aria2 {
 
 class BtContext;
+class BtRuntime;
+class PeerStorage;
 class DHTTask;
 class DHTNode;
 class DHTBucket;
@@ -59,7 +61,9 @@ public:
   virtual SharedHandle<DHTTask> createBucketRefreshTask() = 0;
 
   virtual SharedHandle<DHTTask>
-  createPeerLookupTask(const SharedHandle<BtContext>& ctx) = 0;
+  createPeerLookupTask(const SharedHandle<BtContext>& ctx,
+		       const SharedHandle<BtRuntime>& btRuntime,
+		       const SharedHandle<PeerStorage>& peerStorage) = 0;
   
   virtual SharedHandle<DHTTask>
   createPeerAnnounceTask(const unsigned char* infoHash) = 0;
diff --git a/src/DHTTaskFactoryImpl.cc b/src/DHTTaskFactoryImpl.cc
index 9e399cd1..d4e93725 100644
--- a/src/DHTTaskFactoryImpl.cc
+++ b/src/DHTTaskFactoryImpl.cc
@@ -84,9 +84,15 @@ DHTTaskFactoryImpl::createBucketRefreshTask()
 }
 
 SharedHandle<DHTTask>
-DHTTaskFactoryImpl::createPeerLookupTask(const SharedHandle<BtContext>& ctx)
+DHTTaskFactoryImpl::createPeerLookupTask
+(const SharedHandle<BtContext>& ctx,
+ const SharedHandle<BtRuntime>& btRuntime,
+ const SharedHandle<PeerStorage>& peerStorage)
 {
   SharedHandle<DHTPeerLookupTask> task(new DHTPeerLookupTask(ctx));
+  // TODO these may be not freed by RequestGroup::releaseRuntimeResource()
+  task->setBtRuntime(btRuntime);
+  task->setPeerStorage(peerStorage);
   setCommonProperty(task);
   return task;
 }
diff --git a/src/DHTTaskFactoryImpl.h b/src/DHTTaskFactoryImpl.h
index d35e5323..9d8c1649 100644
--- a/src/DHTTaskFactoryImpl.h
+++ b/src/DHTTaskFactoryImpl.h
@@ -77,7 +77,9 @@ public:
   virtual SharedHandle<DHTTask> createBucketRefreshTask();
 
   virtual SharedHandle<DHTTask>
-  createPeerLookupTask(const SharedHandle<BtContext>& ctx);
+  createPeerLookupTask(const SharedHandle<BtContext>& ctx,
+		       const SharedHandle<BtRuntime>& btRuntime,
+		       const SharedHandle<PeerStorage>& peerStorage);
 
   virtual SharedHandle<DHTTask>
   createPeerAnnounceTask(const unsigned char* infoHash);
diff --git a/src/DefaultBtAnnounce.cc b/src/DefaultBtAnnounce.cc
index 6b9b9784..3d16b892 100644
--- a/src/DefaultBtAnnounce.cc
+++ b/src/DefaultBtAnnounce.cc
@@ -33,7 +33,6 @@
  */
 /* copyright --> */
 #include "DefaultBtAnnounce.h"
-#include "BtRegistry.h"
 #include "LogFactory.h"
 #include "Logger.h"
 #include "MetaFileUtil.h"
@@ -68,10 +67,7 @@ DefaultBtAnnounce::DefaultBtAnnounce(const BtContextHandle& btContext,
   announceList(btContext->getAnnounceTiers()),
   option(option),
   logger(LogFactory::getInstance()),
-  _randomizer(SimpleRandomizer::getInstance()),
-  btRuntime(BT_RUNTIME(btContext)),
-  pieceStorage(PIECE_STORAGE(btContext)),
-  peerStorage(PEER_STORAGE(btContext))
+  _randomizer(SimpleRandomizer::getInstance())
 {
   prevAnnounceTime.setTimeInSec(0);
   generateKey();
diff --git a/src/DefaultBtInteractive.cc b/src/DefaultBtInteractive.cc
index 776271d6..a32a6c3a 100644
--- a/src/DefaultBtInteractive.cc
+++ b/src/DefaultBtInteractive.cc
@@ -33,6 +33,9 @@
  */
 /* copyright --> */
 #include "DefaultBtInteractive.h"
+
+#include <cstring>
+
 #include "prefs.h"
 #include "message.h"
 #include "BtHandshakeMessage.h"
@@ -47,9 +50,7 @@
 #include "HandshakeExtensionMessage.h"
 #include "UTPexExtensionMessage.h"
 #include "DefaultExtensionMessageFactory.h"
-#include "BtRegistry.h"
 #include "DHTNode.h"
-#include "PeerObject.h"
 #include "Peer.h"
 #include "Piece.h"
 #include "BtContext.h"
@@ -61,17 +62,17 @@
 #include "BtMessageFactory.h"
 #include "BtRequestFactory.h"
 #include "PeerConnection.h"
-#include "BtRegistry.h"
 #include "Logger.h"
 #include "LogFactory.h"
 #include "StringFormat.h"
 #include "RequestGroup.h"
-#include <cstring>
 
 namespace aria2 {
 
-DefaultBtInteractive::DefaultBtInteractive(const SharedHandle<BtContext>& btContext, const SharedHandle<Peer>& peer):
-  BtContextAwareCommand(btContext),
+DefaultBtInteractive::DefaultBtInteractive
+(const SharedHandle<BtContext>& btContext, const SharedHandle<Peer>& peer)
+  :
+  _btContext(btContext),
   peer(peer),
   logger(LogFactory::getInstance()),
   allowedFastSetSize(10),
@@ -84,11 +85,10 @@ DefaultBtInteractive::DefaultBtInteractive(const SharedHandle<BtContext>& btCont
 
 DefaultBtInteractive::~DefaultBtInteractive() {}
 
-
 void DefaultBtInteractive::initiateHandshake() {
   SharedHandle<BtMessage> message =
-    messageFactory->createHandshakeMessage(btContext->getInfoHash(),
-					   btContext->getPeerId());
+    messageFactory->createHandshakeMessage(_btContext->getInfoHash(),
+					   _btContext->getPeerId());
   dispatcher->addMessageToQueue(message);
   dispatcher->sendMessages();
 }
@@ -99,8 +99,11 @@ BtMessageHandle DefaultBtInteractive::receiveHandshake(bool quickReply) {
   if(message.isNull()) {
     return SharedHandle<BtMessage>();
   }
-  if(memcmp(message->getPeerId(), btContext->getPeerId(), PEER_ID_LENGTH) == 0) {
-    throw DlAbortEx(StringFormat("CUID#%d - Drop connection from the same Peer ID", cuid).str());
+  if(memcmp(message->getPeerId(), _btContext->getPeerId(),
+	    PEER_ID_LENGTH) == 0) {
+    throw DlAbortEx
+      (StringFormat
+       ("CUID#%d - Drop connection from the same Peer ID", cuid).str());
   }
 
   peer->setPeerId(message->getPeerId());
@@ -111,12 +114,9 @@ BtMessageHandle DefaultBtInteractive::receiveHandshake(bool quickReply) {
   }
   if(message->isExtendedMessagingEnabled()) {
     peer->setExtendedMessagingEnabled(true);
-    DefaultExtensionMessageFactoryHandle factory
-      (new DefaultExtensionMessageFactory(btContext, peer));
     if(!_utPexEnabled) {
-      factory->removeExtension("ut_pex");
+      _extensionMessageFactory->removeExtension("ut_pex");
     }
-    PEER_OBJECT(btContext, peer)->extensionMessageFactory = factory;
     logger->info(MSG_EXTENDED_MESSAGING_ENABLED, cuid);
   }
   if(message->isDHTEnabled()) {
@@ -152,7 +152,8 @@ void DefaultBtInteractive::doPostHandshakeProcessing() {
 
 void DefaultBtInteractive::addPortMessageToQueue()
 {
-  dispatcher->addMessageToQueue(messageFactory->createPortMessage(_localNode->getPort()));
+  dispatcher->addMessageToQueue
+    (messageFactory->createPortMessage(_localNode->getPort()));
 }
 
 void DefaultBtInteractive::addHandshakeExtendedMessageToQueue()
@@ -160,8 +161,8 @@ void DefaultBtInteractive::addHandshakeExtendedMessageToQueue()
   static const std::string CLIENT_ARIA2("aria2");
   HandshakeExtensionMessageHandle m(new HandshakeExtensionMessage());
   m->setClientVersion(CLIENT_ARIA2);
-  m->setTCPPort(btRuntime->getListenPort());
-  m->setExtensions(EXTENSION_MESSAGE_FACTORY(btContext, peer)->getExtensions());
+  m->setTCPPort(_btRuntime->getListenPort());
+  m->setExtensions(_extensionMessageFactory->getExtensions());
   
   SharedHandle<BtMessage> msg = messageFactory->createBtExtendedMessage(m);
   dispatcher->addMessageToQueue(msg);
@@ -169,15 +170,15 @@ void DefaultBtInteractive::addHandshakeExtendedMessageToQueue()
 
 void DefaultBtInteractive::addBitfieldMessageToQueue() {
   if(peer->isFastExtensionEnabled()) {
-    if(pieceStorage->allDownloadFinished()) {
+    if(_pieceStorage->allDownloadFinished()) {
       dispatcher->addMessageToQueue(messageFactory->createHaveAllMessage());
-    } else if(pieceStorage->getCompletedLength() > 0) {
+    } else if(_pieceStorage->getCompletedLength() > 0) {
       dispatcher->addMessageToQueue(messageFactory->createBitfieldMessage());
     } else {
       dispatcher->addMessageToQueue(messageFactory->createHaveNoneMessage());
     }
   } else {
-    if(pieceStorage->getCompletedLength() > 0) {
+    if(_pieceStorage->getCompletedLength() > 0) {
       dispatcher->addMessageToQueue(messageFactory->createBitfieldMessage());
     }
   }
@@ -186,10 +187,11 @@ void DefaultBtInteractive::addBitfieldMessageToQueue() {
 void DefaultBtInteractive::addAllowedFastMessageToQueue() {
   if(peer->isFastExtensionEnabled()) {
     std::deque<size_t> fastSet;
-    btContext->computeFastSet(fastSet, peer->ipaddr, allowedFastSetSize);
+    _btContext->computeFastSet(fastSet, peer->ipaddr, allowedFastSetSize);
     for(std::deque<size_t>::const_iterator itr = fastSet.begin();
 	itr != fastSet.end(); itr++) {
-      dispatcher->addMessageToQueue(messageFactory->createAllowedFastMessage(*itr));
+      dispatcher->addMessageToQueue
+	(messageFactory->createAllowedFastMessage(*itr));
     }
   }
 }
@@ -208,16 +210,17 @@ void DefaultBtInteractive::decideChoking() {
 
 void DefaultBtInteractive::checkHave() {
   std::deque<size_t> indexes;
-  pieceStorage->getAdvertisedPieceIndexes(indexes, cuid, haveCheckPoint);
+  _pieceStorage->getAdvertisedPieceIndexes(indexes, cuid, haveCheckPoint);
   haveCheckPoint.reset();
   if(indexes.size() >= 20) {
-    if(peer->isFastExtensionEnabled() && pieceStorage->allDownloadFinished()) {
+    if(peer->isFastExtensionEnabled() && _pieceStorage->allDownloadFinished()) {
       dispatcher->addMessageToQueue(messageFactory->createHaveAllMessage());
     } else {
       dispatcher->addMessageToQueue(messageFactory->createBitfieldMessage());
     }
   } else {
-    for(std::deque<size_t>::iterator itr = indexes.begin(); itr != indexes.end(); itr++) {
+    for(std::deque<size_t>::iterator itr = indexes.begin();
+	itr != indexes.end(); itr++) {
       dispatcher->addMessageToQueue(messageFactory->createHaveMessage(*itr));
     }
   }
@@ -235,7 +238,7 @@ size_t DefaultBtInteractive::receiveMessages() {
   size_t msgcount = 0;
   for(int i = 0; i < 50; i++) {
     if(maxDownloadSpeedLimit > 0) {
-      TransferStat stat = btContext->getOwnerRequestGroup()->calculateStat();
+      TransferStat stat = _btContext->getOwnerRequestGroup()->calculateStat();
       if(maxDownloadSpeedLimit < stat.downloadSpeed) {
 	break;
       }
@@ -274,7 +277,7 @@ size_t DefaultBtInteractive::receiveMessages() {
 }
 
 void DefaultBtInteractive::decideInterest() {
-  if(pieceStorage->hasMissingPiece(peer)) {
+  if(_pieceStorage->hasMissingPiece(peer)) {
     if(!peer->amInterested()) {
       logger->debug(MSG_PEER_INTERESTED, cuid);
       dispatcher->
@@ -290,7 +293,7 @@ void DefaultBtInteractive::decideInterest() {
 }
 
 void DefaultBtInteractive::fillPiece(size_t maxMissingBlock) {
-  if(pieceStorage->hasMissingPiece(peer)) {
+  if(_pieceStorage->hasMissingPiece(peer)) {
 
     size_t numMissingBlock = btRequestFactory->countMissingBlock();
 
@@ -300,7 +303,7 @@ void DefaultBtInteractive::fillPiece(size_t maxMissingBlock) {
 	btRequestFactory->getTargetPieceIndexes(excludedIndexes);
 	while(numMissingBlock < maxMissingBlock) {
 	  SharedHandle<Piece> piece =
-	    pieceStorage->getMissingFastPiece(peer, excludedIndexes);
+	    _pieceStorage->getMissingFastPiece(peer, excludedIndexes);
 	  if(piece.isNull()) {
 	    break;
 	  } else {
@@ -315,7 +318,7 @@ void DefaultBtInteractive::fillPiece(size_t maxMissingBlock) {
       btRequestFactory->getTargetPieceIndexes(excludedIndexes);
       while(numMissingBlock < maxMissingBlock) {
 	SharedHandle<Piece> piece =
-	  pieceStorage->getMissingPiece(peer, excludedIndexes);
+	  _pieceStorage->getMissingPiece(peer, excludedIndexes);
 	if(piece.isNull()) {
 	  break;
 	} else {
@@ -344,7 +347,7 @@ void DefaultBtInteractive::addRequests() {
     0 : MAX_PENDING_REQUEST-dispatcher->countOutstandingRequest();
   if(reqNumToCreate > 0) {
     BtMessages requests;
-    if(pieceStorage->isEndGame()) {
+    if(_pieceStorage->isEndGame()) {
       btRequestFactory->createRequestMessagesOnEndGame(requests, reqNumToCreate);
     } else {
       btRequestFactory->createRequestMessages(requests, reqNumToCreate);
@@ -383,7 +386,8 @@ void DefaultBtInteractive::checkActiveInteraction()
        inactiveCheckPoint.elapsed(interval)) {
       // TODO change the message
       throw DlAbortEx
-	(StringFormat("Disconnect peer because we are not interested each other after %u second(s).", interval).str());
+	(StringFormat("Disconnect peer because we are not interested each other"
+		      " after %u second(s).", interval).str());
     }
   }
   // Since the peers which are *just* connected and do nothing to improve
@@ -403,7 +407,7 @@ void DefaultBtInteractive::addPeerExchangeMessage()
   if(_pexCheckPoint.elapsed(UTPexExtensionMessage::DEFAULT_INTERVAL)) {
     UTPexExtensionMessageHandle m
       (new UTPexExtensionMessage(peer->getExtensionMessageID("ut_pex")));
-    const Peers& peers = peerStorage->getPeers();
+    const Peers& peers = _peerStorage->getPeers();
     {
       for(std::deque<SharedHandle<Peer> >::const_iterator i =
 	    peers.begin(); i != peers.end() && !m->freshPeersAreFull(); ++i) {
@@ -445,7 +449,7 @@ void DefaultBtInteractive::doInteractionProcessing() {
   btRequestFactory->removeCompletedPiece();
 
   decideInterest();
-  if(!pieceStorage->downloadFinished()) {
+  if(!_pieceStorage->downloadFinished()) {
     addRequests();
   }
 
@@ -481,32 +485,61 @@ size_t DefaultBtInteractive::countOutstandingRequest()
   return dispatcher->countOutstandingRequest();
 }
 
+void DefaultBtInteractive::setBtRuntime
+(const SharedHandle<BtRuntime>& btRuntime)
+{
+  _btRuntime = btRuntime;
+}
+
+void DefaultBtInteractive::setPieceStorage
+(const SharedHandle<PieceStorage>& pieceStorage)
+{
+  _pieceStorage = pieceStorage;
+}
+
+void DefaultBtInteractive::setPeerStorage
+(const SharedHandle<PeerStorage>& peerStorage)
+{
+  _peerStorage = peerStorage;
+}
+
 void DefaultBtInteractive::setPeer(const SharedHandle<Peer>& peer)
 {
   this->peer = peer;
 }
 
-void DefaultBtInteractive::setBtMessageReceiver(const BtMessageReceiverWeakHandle& receiver)
+void DefaultBtInteractive::setBtMessageReceiver
+(const SharedHandle<BtMessageReceiver>& receiver)
 {
   this->btMessageReceiver = receiver;
 }
 
-void DefaultBtInteractive::setDispatcher(const BtMessageDispatcherWeakHandle& dispatcher)
+void DefaultBtInteractive::setDispatcher
+(const SharedHandle<BtMessageDispatcher>& dispatcher)
 {
   this->dispatcher = dispatcher;
 }
 
-void DefaultBtInteractive::setBtRequestFactory(const BtRequestFactoryWeakHandle& factory)
+void DefaultBtInteractive::setBtRequestFactory
+(const SharedHandle<BtRequestFactory>& factory)
 {
   this->btRequestFactory = factory;
 }
 
-void DefaultBtInteractive::setPeerConnection(const PeerConnectionWeakHandle& peerConnection)
+void DefaultBtInteractive::setPeerConnection
+(const SharedHandle<PeerConnection>& peerConnection)
 {
   this->peerConnection  = peerConnection;
 }
 
-void DefaultBtInteractive::setBtMessageFactory(const BtMessageFactoryWeakHandle& factory)
+void DefaultBtInteractive::setExtensionMessageFactory
+(const SharedHandle<ExtensionMessageFactory>& factory)
+{
+  _extensionMessageFactory = factory;
+}
+
+void DefaultBtInteractive::setBtMessageFactory
+(const SharedHandle<BtMessageFactory>& factory)
 {
   this->messageFactory = factory;
 }
diff --git a/src/DefaultBtInteractive.h b/src/DefaultBtInteractive.h
index f7f47a33..98f9d2e3 100644
--- a/src/DefaultBtInteractive.h
+++ b/src/DefaultBtInteractive.h
@@ -36,12 +36,17 @@
 #define _D_DEFAULT_BT_INTERACTIVE_H_
 
 #include "BtInteractive.h"
-#include "BtContextAwareCommand.h"
-#include "TimeA2.h"
+
 #include  <limits.h>
 
+#include "TimeA2.h"
+
 namespace aria2 {
 
+class BtContext;
+class BtRuntime;
+class PieceStorage;
+class PeerStorage;
 class Peer;
 class BtMessage;
 class BtMessageReceiver;
@@ -49,6 +54,7 @@ class BtMessageDispatcher;
 class BtMessageFactory;
 class BtRequestFactory;
 class PeerConnection;
+class ExtensionMessageFactory;
 class DHTNode;
 class Logger;
 
@@ -85,16 +91,26 @@ public:
   }
 };
 
-class DefaultBtInteractive : public BtInteractive, public BtContextAwareCommand {
+class DefaultBtInteractive : public BtInteractive {
 private:
   int32_t cuid;
+
+  SharedHandle<BtContext> _btContext;
+
+  SharedHandle<BtRuntime> _btRuntime;
+
+  SharedHandle<PieceStorage> _pieceStorage;
+
+  SharedHandle<PeerStorage> _peerStorage;
+
   SharedHandle<Peer> peer;
 
-  WeakHandle<BtMessageReceiver> btMessageReceiver;
-  WeakHandle<BtMessageDispatcher> dispatcher;
-  WeakHandle<BtRequestFactory> btRequestFactory;
-  WeakHandle<PeerConnection> peerConnection;
-  WeakHandle<BtMessageFactory> messageFactory;
+  SharedHandle<BtMessageReceiver> btMessageReceiver;
+  SharedHandle<BtMessageDispatcher> dispatcher;
+  SharedHandle<BtRequestFactory> btRequestFactory;
+  SharedHandle<PeerConnection> peerConnection;
+  SharedHandle<BtMessageFactory> messageFactory;
+  SharedHandle<ExtensionMessageFactory> _extensionMessageFactory;
 
   WeakHandle<DHTNode> _localNode;
 
@@ -163,17 +179,26 @@ public:
     this->cuid = cuid;
   }
 
+  void setBtRuntime(const SharedHandle<BtRuntime>& btRuntime);
+
+  void setPieceStorage(const SharedHandle<PieceStorage>& pieceStorage);
+
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
+
   void setPeer(const SharedHandle<Peer>& peer);
 
-  void setBtMessageReceiver(const WeakHandle<BtMessageReceiver>& receiver);
+  void setBtMessageReceiver(const SharedHandle<BtMessageReceiver>& receiver);
+
+  void setDispatcher(const SharedHandle<BtMessageDispatcher>& dispatcher);
 
-  void setDispatcher(const WeakHandle<BtMessageDispatcher>& dispatcher);
+  void setBtRequestFactory(const SharedHandle<BtRequestFactory>& factory);
 
-  void setBtRequestFactory(const WeakHandle<BtRequestFactory>& factory);
+  void setPeerConnection(const SharedHandle<PeerConnection>& peerConnection);
 
-  void setPeerConnection(const WeakHandle<PeerConnection>& peerConnection);
+  void setBtMessageFactory(const SharedHandle<BtMessageFactory>& factory);
 
-  void setBtMessageFactory(const WeakHandle<BtMessageFactory>& factory);
+  void setExtensionMessageFactory
+  (const SharedHandle<ExtensionMessageFactory>& factory);
 
   void setKeepAliveInterval(time_t keepAliveInterval) {
     this->keepAliveInterval = keepAliveInterval;
diff --git a/src/DefaultBtMessageDispatcher.cc b/src/DefaultBtMessageDispatcher.cc
index 55980bc0..07d54722 100644
--- a/src/DefaultBtMessageDispatcher.cc
+++ b/src/DefaultBtMessageDispatcher.cc
@@ -33,6 +33,9 @@
  */
 /* copyright --> */
 #include "DefaultBtMessageDispatcher.h"
+
+#include <algorithm>
+
 #include "prefs.h"
 #include "BtAbortOutstandingRequestEvent.h"
 #include "BtCancelSendingPieceEvent.h"
@@ -44,13 +47,11 @@
 #include "PeerStorage.h"
 #include "PieceStorage.h"
 #include "BtMessage.h"
-#include "BtRegistry.h"
 #include "Peer.h"
 #include "Piece.h"
 #include "LogFactory.h"
 #include "Logger.h"
 #include "a2functional.h"
-#include <algorithm>
 
 namespace aria2 {
 
@@ -86,7 +87,7 @@ void DefaultBtMessageDispatcher::sendMessages() {
     messageQueue.pop_front();
     if(maxUploadSpeedLimit > 0 &&
        msg->isUploading() && !msg->isSendingInProgress()) {
-      TransferStat stat = peerStorage->calculateStat();
+      TransferStat stat = _peerStorage->calculateStat();
       if(maxUploadSpeedLimit < stat.getUploadSpeed()) {
 	tempQueue.push_back(msg);
 	continue;
@@ -228,7 +229,7 @@ public:
 void DefaultBtMessageDispatcher::doChokedAction()
 {
   std::for_each(requestSlots.begin(), requestSlots.end(),
-		ProcessChokedRequestSlot(cuid, peer, pieceStorage));
+		ProcessChokedRequestSlot(cuid, peer, _pieceStorage));
 
   requestSlots.erase(std::remove_if(requestSlots.begin(), requestSlots.end(),
 				    FindChokedRequestSlot(peer)),
@@ -332,13 +333,13 @@ void DefaultBtMessageDispatcher::checkRequestSlotAndDoNecessaryThing()
   std::for_each(requestSlots.begin(), requestSlots.end(),
 		ProcessStaleRequestSlot(cuid,
 					peer,
-					pieceStorage,
+					_pieceStorage,
 					this,
 					messageFactory,
 					now,
 					requestTimeout));
   requestSlots.erase(std::remove_if(requestSlots.begin(), requestSlots.end(),
-				    FindStaleRequestSlot(pieceStorage,
+				    FindStaleRequestSlot(_pieceStorage,
 							 now,
 							 requestTimeout)),
 		     requestSlots.end());
@@ -437,8 +438,18 @@ void DefaultBtMessageDispatcher::setPeer(const SharedHandle<Peer>& peer)
 void DefaultBtMessageDispatcher::setBtContext(const BtContextHandle& btContext)
 {
   this->btContext = btContext;
-  this->pieceStorage = PIECE_STORAGE(btContext);
-  this->peerStorage = PEER_STORAGE(btContext);
+}
+
+void DefaultBtMessageDispatcher::setPieceStorage
+(const SharedHandle<PieceStorage>& pieceStorage)
+{
+  _pieceStorage = pieceStorage;
+}
+
+void DefaultBtMessageDispatcher::setPeerStorage
+(const SharedHandle<PeerStorage>& peerStorage)
+{
+  _peerStorage = peerStorage;
 }
 
 void DefaultBtMessageDispatcher::setBtMessageFactory(const WeakHandle<BtMessageFactory>& factory)
diff --git a/src/DefaultBtMessageDispatcher.h b/src/DefaultBtMessageDispatcher.h
index bfd3925a..678bfa5f 100644
--- a/src/DefaultBtMessageDispatcher.h
+++ b/src/DefaultBtMessageDispatcher.h
@@ -55,8 +55,8 @@ private:
   std::deque<SharedHandle<BtMessage> > messageQueue;
   std::deque<RequestSlot> requestSlots;
   SharedHandle<BtContext> btContext;
-  SharedHandle<PeerStorage> peerStorage;
-  SharedHandle<PieceStorage> pieceStorage;
+  SharedHandle<PeerStorage> _peerStorage;
+  SharedHandle<PieceStorage> _pieceStorage;
   WeakHandle<BtMessageFactory> messageFactory;
   SharedHandle<Peer> peer;
   unsigned int maxUploadSpeedLimit;
@@ -111,6 +111,10 @@ public:
 
   void setBtContext(const SharedHandle<BtContext>& btContext);
 
+  void setPieceStorage(const SharedHandle<PieceStorage>& pieceStorage);
+
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
+
   void setBtMessageFactory(const WeakHandle<BtMessageFactory>& factory);
 
   void setCuid(int32_t cuid) {
diff --git a/src/DefaultBtMessageFactory.cc b/src/DefaultBtMessageFactory.cc
index b35f8df2..6cba336f 100644
--- a/src/DefaultBtMessageFactory.cc
+++ b/src/DefaultBtMessageFactory.cc
@@ -65,10 +65,11 @@
 #include "ExtensionMessage.h"
 #include "Peer.h"
 #include "Piece.h"
-#include "BtRegistry.h"
 #include "BtContext.h"
 #include "PieceStorage.h"
+#include "PeerStorage.h"
 #include "StringFormat.h"
+#include "ExtensionMessageFactory.h"
 
 namespace aria2 {
 
@@ -98,7 +99,12 @@ DefaultBtMessageFactory::createBtMessage(const unsigned char* data, size_t dataL
       msg = BtInterestedMessage::create(data, dataLength);
       break;
     case BtNotInterestedMessage::ID:
-      msg = BtNotInterestedMessage::create(data, dataLength);
+      {
+	SharedHandle<BtNotInterestedMessage> m =
+	  BtNotInterestedMessage::create(data, dataLength);
+	m->setPeerStorage(_peerStorage);
+	msg = m;
+      }
       break;
     case BtHaveMessage::ID:
       msg = BtHaveMessage::create(data, dataLength);
@@ -123,7 +129,7 @@ DefaultBtMessageFactory::createBtMessage(const unsigned char* data, size_t dataL
       BtMessageValidatorHandle validator
 	(new BtRequestMessageValidator(temp.get(),
 				      btContext->getNumPieces(),
-				       pieceStorage->getPieceLength(temp->getIndex())));
+				       _pieceStorage->getPieceLength(temp->getIndex())));
       temp->setBtMessageValidator(validator);
       msg = temp;
       break;
@@ -133,7 +139,7 @@ DefaultBtMessageFactory::createBtMessage(const unsigned char* data, size_t dataL
       BtMessageValidatorHandle validator
 	(new BtCancelMessageValidator(temp.get(),
 				     btContext->getNumPieces(),
-				      pieceStorage->getPieceLength(temp->getIndex())));
+				      _pieceStorage->getPieceLength(temp->getIndex())));
       temp->setBtMessageValidator(validator);
       msg = temp;
       break;
@@ -143,7 +149,7 @@ DefaultBtMessageFactory::createBtMessage(const unsigned char* data, size_t dataL
       BtMessageValidatorHandle validator
 	(new BtPieceMessageValidator(temp.get(),
 				     btContext->getNumPieces(),
-				     pieceStorage->getPieceLength(temp->getIndex())));
+				     _pieceStorage->getPieceLength(temp->getIndex())));
       temp->setBtMessageValidator(validator);
       msg = temp;
       break;
@@ -159,7 +165,7 @@ DefaultBtMessageFactory::createBtMessage(const unsigned char* data, size_t dataL
       BtMessageValidatorHandle validator
 	(new BtRejectMessageValidator(temp.get(),
 				      btContext->getNumPieces(),
-				      pieceStorage->getPieceLength(temp->getIndex())));
+				      _pieceStorage->getPieceLength(temp->getIndex())));
       temp->setBtMessageValidator(validator);
       msg = temp;
       break;
@@ -193,7 +199,8 @@ DefaultBtMessageFactory::createBtMessage(const unsigned char* data, size_t dataL
     }
     case BtExtendedMessage::ID: {
       if(peer->isExtendedMessagingEnabled()) {
-	msg = BtExtendedMessage::create(btContext, peer, data, dataLength);
+	msg = BtExtendedMessage::create(_extensionMessageFactory,
+					peer, data, dataLength);
       } else {
 	throw DlAbortEx("Received extended message from peer during a session with extended messaging disabled.");
       }
@@ -211,6 +218,7 @@ void DefaultBtMessageFactory::setCommonProperty(const AbstractBtMessageHandle& m
   msg->setCuid(cuid);
   msg->setPeer(peer);
   msg->setBtContext(btContext);
+  msg->setPieceStorage(_pieceStorage);
   msg->setBtMessageDispatcher(dispatcher);
   msg->setBtRequestFactory(requestFactory);
   msg->setBtMessageFactory(WeakHandle<BtMessageFactory>(this));
@@ -254,7 +262,7 @@ DefaultBtMessageFactory::createRequestMessage(const PieceHandle& piece, size_t b
   BtMessageValidatorHandle validator
     (new BtRequestMessageValidator(msg.get(),
 				   btContext->getNumPieces(),
-				   pieceStorage->getPieceLength(msg->getIndex())));
+				   _pieceStorage->getPieceLength(msg->getIndex())));
   msg->setBtMessageValidator(validator);
   setCommonProperty(msg);
   return msg;
@@ -267,7 +275,7 @@ DefaultBtMessageFactory::createCancelMessage(size_t index, uint32_t begin, size_
   BtMessageValidatorHandle validator
     (new BtCancelMessageValidator(msg.get(),
 				  btContext->getNumPieces(),
-				  pieceStorage->getPieceLength(index)));
+				  _pieceStorage->getPieceLength(index)));
   msg->setBtMessageValidator(validator);
   setCommonProperty(msg);
   return msg;
@@ -280,7 +288,7 @@ DefaultBtMessageFactory::createPieceMessage(size_t index, uint32_t begin, size_t
   BtMessageValidatorHandle validator
     (new BtPieceMessageValidator(msg.get(),
 				btContext->getNumPieces(),
-				pieceStorage->getPieceLength(index)));
+				_pieceStorage->getPieceLength(index)));
   msg->setBtMessageValidator(validator);
   setCommonProperty(msg);
   return msg;
@@ -334,8 +342,8 @@ BtMessageHandle
 DefaultBtMessageFactory::createBitfieldMessage()
 {
   BtBitfieldMessageHandle msg
-    (new BtBitfieldMessage(pieceStorage->getBitfield(),
-			   pieceStorage->getBitfieldLength()));
+    (new BtBitfieldMessage(_pieceStorage->getBitfield(),
+			   _pieceStorage->getBitfieldLength()));
   SharedHandle<BtMessageValidator> v
     (new BtBitfieldMessageValidator(msg.get(),
 				    btContext->getNumPieces()));
@@ -375,7 +383,7 @@ DefaultBtMessageFactory::createRejectMessage(size_t index, uint32_t begin, size_
   BtMessageValidatorHandle validator
     (new BtRejectMessageValidator(msg.get(),
 				  btContext->getNumPieces(),
-				  pieceStorage->getPieceLength(index)));
+				  _pieceStorage->getPieceLength(index)));
   msg->setBtMessageValidator(validator);
   setCommonProperty(msg);
   return msg;
@@ -427,7 +435,18 @@ void DefaultBtMessageFactory::setPeer(const SharedHandle<Peer>& peer)
 void DefaultBtMessageFactory::setBtContext(const SharedHandle<BtContext>& btContext)
 {
   this->btContext = btContext;
-  this->pieceStorage = PIECE_STORAGE(btContext);
+}
+
+void DefaultBtMessageFactory::setPieceStorage
+(const SharedHandle<PieceStorage>& pieceStorage)
+{
+  _pieceStorage = pieceStorage;
+}
+
+void DefaultBtMessageFactory::setPeerStorage
+(const SharedHandle<PeerStorage>& peerStorage)
+{
+  _peerStorage = peerStorage;
 }
 
 void DefaultBtMessageFactory::setBtMessageDispatcher(const WeakHandle<BtMessageDispatcher>& dispatcher)
@@ -435,6 +454,12 @@ void DefaultBtMessageFactory::setBtMessageDispatcher(const WeakHandle<BtMessageD
   this->dispatcher = dispatcher;
 }
 
+void DefaultBtMessageFactory::setExtensionMessageFactory
+(const SharedHandle<ExtensionMessageFactory>& factory)
+{
+  _extensionMessageFactory = factory;
+}
+
 void DefaultBtMessageFactory::setLocalNode(const WeakHandle<DHTNode>& localNode)
 {
   _localNode = localNode;
diff --git a/src/DefaultBtMessageFactory.h b/src/DefaultBtMessageFactory.h
index d0de2dd4..c2ef06fc 100644
--- a/src/DefaultBtMessageFactory.h
+++ b/src/DefaultBtMessageFactory.h
@@ -40,12 +40,14 @@
 namespace aria2 {
 
 class BtContext;
+class PieceStorage;
+class PeerStorage;
 class Peer;
 class AbstractBtMessage;
 class BtMessageDispatcher;
 class BtRequestFactory;
 class PeerConnection;
-class PieceStorage;
+class ExtensionMessageFactory;
 class DHTNode;
 class DHTRoutingTable;
 class DHTTaskQueue;
@@ -55,7 +57,8 @@ class DefaultBtMessageFactory : public BtMessageFactory {
 private:
   int32_t cuid;
   SharedHandle<BtContext> btContext;
-  SharedHandle<PieceStorage> pieceStorage;
+  SharedHandle<PieceStorage> _pieceStorage;
+  SharedHandle<PeerStorage> _peerStorage;
   SharedHandle<Peer> peer;
 
   bool _dhtEnabled;
@@ -66,6 +69,8 @@ private:
 
   WeakHandle<PeerConnection> peerConnection;
 
+  SharedHandle<ExtensionMessageFactory> _extensionMessageFactory;
+
   WeakHandle<DHTNode> _localNode;
 
   WeakHandle<DHTRoutingTable> _routingTable;
@@ -131,6 +136,10 @@ public:
 
   void setBtContext(const SharedHandle<BtContext>& btContext);
 
+  void setPieceStorage(const SharedHandle<PieceStorage>& pieceStorage);
+
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
+
   void setCuid(int32_t cuid) {
     this->cuid = cuid;
   }
@@ -145,6 +154,9 @@ public:
 
   void setPeerConnection(const WeakHandle<PeerConnection>& connection);
 
+  void setExtensionMessageFactory
+  (const SharedHandle<ExtensionMessageFactory>& factory);
+
   void setLocalNode(const WeakHandle<DHTNode>& localNode);
 
   void setRoutingTable(const WeakHandle<DHTRoutingTable>& routingTable);
diff --git a/src/DefaultBtMessageReceiver.cc b/src/DefaultBtMessageReceiver.cc
index 973beaf3..d6afbb70 100644
--- a/src/DefaultBtMessageReceiver.cc
+++ b/src/DefaultBtMessageReceiver.cc
@@ -33,17 +33,18 @@
  */
 /* copyright --> */
 #include "DefaultBtMessageReceiver.h"
+
+#include <cstring>
+
 #include "BtHandshakeMessage.h"
 #include "message.h"
 #include "BtContext.h"
-#include "BtRegistry.h"
 #include "Peer.h"
 #include "PeerConnection.h"
 #include "BtMessageDispatcher.h"
 #include "BtMessageFactory.h"
 #include "Logger.h"
 #include "LogFactory.h"
-#include <cstring>
 
 namespace aria2 {
 
diff --git a/src/DefaultBtProgressInfoFile.cc b/src/DefaultBtProgressInfoFile.cc
index eb93a3ed..31286de9 100644
--- a/src/DefaultBtProgressInfoFile.cc
+++ b/src/DefaultBtProgressInfoFile.cc
@@ -33,6 +33,11 @@
  */
 /* copyright --> */
 #include "DefaultBtProgressInfoFile.h"
+
+#include <cerrno>
+#include <cstring>
+#include <fstream>
+
 #include "BtContext.h"
 #include "PieceStorage.h"
 #include "Piece.h"
@@ -41,7 +46,6 @@
 #include "BitfieldMan.h"
 #include "Option.h"
 #include "TransferStat.h"
-#include "BtRegistry.h"
 #include "LogFactory.h"
 #include "Logger.h"
 #include "prefs.h"
@@ -52,9 +56,6 @@
 #include "a2io.h"
 #include "DownloadFailureException.h"
 #include "StringFormat.h"
-#include <fstream>
-#include <cerrno>
-#include <cstring>
 
 namespace aria2 {
 
@@ -86,7 +87,7 @@ void DefaultBtProgressInfoFile::updateFilename()
 
 bool DefaultBtProgressInfoFile::isTorrentDownload()
 {
-  return !dynamic_pointer_cast<BtContext>(_dctx).isNull();
+  return !_btRuntime.isNull();
 }
 
 // Since version 0001, Integers are saved in binary form, network byte order.
@@ -138,8 +139,7 @@ void DefaultBtProgressInfoFile::save() {
     // uploadLength: 64 bits
     uint64_t uploadLengthNL = 0;
     if(torrentDownload) {
-      BtContextHandle btContext(dynamic_pointer_cast<BtContext>(_dctx));
-      TransferStat stat = PEER_STORAGE(btContext)->calculateStat();
+      TransferStat stat = _peerStorage->calculateStat();
       uploadLengthNL = hton64(stat.getAllTimeUploadLength());
     }
     o.write(reinterpret_cast<const char*>(&uploadLengthNL),
@@ -267,8 +267,7 @@ void DefaultBtProgressInfoFile::load()
       uploadLength = ntoh64(uploadLength);
     }
     if(isTorrentDownload()) {
-      BT_RUNTIME(dynamic_pointer_cast<BtContext>(_dctx))->
-	setUploadLengthAtStartup(uploadLength);
+      _btRuntime->setUploadLengthAtStartup(uploadLength);
     }
 
     // TODO implement the conversion mechanism between different piece length.
@@ -401,4 +400,16 @@ bool DefaultBtProgressInfoFile::exists()
   }
 }
 
+void DefaultBtProgressInfoFile::setPeerStorage
+(const SharedHandle<PeerStorage>& peerStorage)
+{
+  _peerStorage = peerStorage;
+}
+
+void DefaultBtProgressInfoFile::setBtRuntime
+(const SharedHandle<BtRuntime>& btRuntime)
+{
+  _btRuntime = btRuntime;
+}
+
 } // namespace aria2
diff --git a/src/DefaultBtProgressInfoFile.h b/src/DefaultBtProgressInfoFile.h
index 72757387..8ea84df2 100644
--- a/src/DefaultBtProgressInfoFile.h
+++ b/src/DefaultBtProgressInfoFile.h
@@ -41,6 +41,8 @@ namespace aria2 {
 
 class DownloadContext;
 class PieceStorage;
+class PeerStorage;
+class BtRuntime;
 class Logger;
 class Option;
 
@@ -48,6 +50,9 @@ class DefaultBtProgressInfoFile : public BtProgressInfoFile {
 private:
   SharedHandle<DownloadContext> _dctx;
   SharedHandle<PieceStorage> _pieceStorage;
+  SharedHandle<PeerStorage> _peerStorage;
+  SharedHandle<BtRuntime> _btRuntime;
+  
   const Option* _option;
   Logger* _logger;
   std::string _filename;
@@ -76,6 +81,10 @@ public:
   // re-set filename using current _dctx.
   virtual void updateFilename();
 
+  // for torrents
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
+
+  void setBtRuntime(const SharedHandle<BtRuntime>& btRuntime);
 };
 
 } // namespace aria2
diff --git a/src/DefaultBtRequestFactory.cc b/src/DefaultBtRequestFactory.cc
index 6227b799..87fbd411 100644
--- a/src/DefaultBtRequestFactory.cc
+++ b/src/DefaultBtRequestFactory.cc
@@ -33,6 +33,9 @@
  */
 /* copyright --> */
 #include "DefaultBtRequestFactory.h"
+
+#include <algorithm>
+
 #include "LogFactory.h"
 #include "Logger.h"
 #include "Piece.h"
@@ -42,9 +45,7 @@
 #include "BtMessageDispatcher.h"
 #include "BtMessageFactory.h"
 #include "BtMessage.h"
-#include "BtRegistry.h"
 #include "a2functional.h"
-#include <algorithm>
 
 namespace aria2 {
 
@@ -93,7 +94,7 @@ void DefaultBtRequestFactory::removeTargetPiece(const PieceHandle& piece) {
   pieces.erase(std::remove(pieces.begin(), pieces.end(), piece),
 	       pieces.end());
   dispatcher->doAbortOutstandingRequestAction(piece);
-  pieceStorage->cancelPiece(piece);
+  _pieceStorage->cancelPiece(piece);
 }
 
 class ProcessChokedPiece {
@@ -129,7 +130,7 @@ public:
 void DefaultBtRequestFactory::doChokedAction()
 {
   std::for_each(pieces.begin(), pieces.end(),
-		ProcessChokedPiece(peer, pieceStorage));
+		ProcessChokedPiece(peer, _pieceStorage));
   pieces.erase(std::remove_if(pieces.begin(), pieces.end(),
 			      FindChokedPiece(peer)),
 	       pieces.end());
@@ -138,7 +139,7 @@ void DefaultBtRequestFactory::doChokedAction()
 void DefaultBtRequestFactory::removeAllTargetPiece() {
   for(Pieces::iterator itr = pieces.begin(); itr != pieces.end(); ++itr) {
     dispatcher->doAbortOutstandingRequestAction(*itr);
-    pieceStorage->cancelPiece(*itr);
+    _pieceStorage->cancelPiece(*itr);
   }
   pieces.clear();
 }
@@ -225,7 +226,12 @@ std::deque<SharedHandle<Piece> >& DefaultBtRequestFactory::getTargetPieces()
 void DefaultBtRequestFactory::setBtContext(const SharedHandle<BtContext>& btContext)
 {
   this->btContext = btContext;
-  this->pieceStorage = PIECE_STORAGE(btContext);
+}
+
+void DefaultBtRequestFactory::setPieceStorage
+(const SharedHandle<PieceStorage>& pieceStorage)
+{
+  _pieceStorage = pieceStorage;
 }
 
 void DefaultBtRequestFactory::setPeer(const SharedHandle<Peer>& peer)
diff --git a/src/DefaultBtRequestFactory.h b/src/DefaultBtRequestFactory.h
index 5067138d..89e1096c 100644
--- a/src/DefaultBtRequestFactory.h
+++ b/src/DefaultBtRequestFactory.h
@@ -51,7 +51,7 @@ class DefaultBtRequestFactory : public BtRequestFactory {
 private:
   int32_t cuid;
   SharedHandle<BtContext> btContext;
-  SharedHandle<PieceStorage> pieceStorage;
+  SharedHandle<PieceStorage> _pieceStorage;
   SharedHandle<Peer> peer;
   WeakHandle<BtMessageDispatcher> dispatcher;
   WeakHandle<BtMessageFactory> messageFactory;
@@ -95,6 +95,8 @@ public:
 
   void setBtContext(const SharedHandle<BtContext>& btContext);
 
+  void setPieceStorage(const SharedHandle<PieceStorage>& pieceStorage);
+
   void setPeer(const SharedHandle<Peer>& peer);
 
   void setBtMessageDispatcher(const WeakHandle<BtMessageDispatcher>& dispatcher);
diff --git a/src/DefaultExtensionMessageFactory.cc b/src/DefaultExtensionMessageFactory.cc
index 2295a70e..b8ccee7e 100644
--- a/src/DefaultExtensionMessageFactory.cc
+++ b/src/DefaultExtensionMessageFactory.cc
@@ -40,8 +40,8 @@
 #include "UTPexExtensionMessage.h"
 #include "LogFactory.h"
 #include "Logger.h"
-#include "BtRegistry.h"
 #include "StringFormat.h"
+#include "PeerStorage.h"
 
 namespace aria2 {
 
@@ -76,8 +76,8 @@ DefaultExtensionMessageFactory::createMessage(const unsigned char* data, size_t
     if(extensionName == "ut_pex") {
       // uTorrent compatible Peer-Exchange
       UTPexExtensionMessageHandle m =
-	UTPexExtensionMessage::create(_btContext, data, length);
-      m->setBtContext(_btContext);
+	UTPexExtensionMessage::create(data, length);
+      m->setPeerStorage(_peerStorage);
       return m;
     } else {
       throw DlAbortEx
@@ -92,6 +92,12 @@ void DefaultExtensionMessageFactory::setBtContext(const BtContextHandle& btConte
   _btContext = btContext;
 }
 
+void DefaultExtensionMessageFactory::setPeerStorage
+(const SharedHandle<PeerStorage>& peerStorage)
+{
+  _peerStorage = peerStorage;
+}
+
 void DefaultExtensionMessageFactory::setPeer(const PeerHandle& peer)
 {
   _peer = peer;
diff --git a/src/DefaultExtensionMessageFactory.h b/src/DefaultExtensionMessageFactory.h
index 6bbc45ef..e1cef02f 100644
--- a/src/DefaultExtensionMessageFactory.h
+++ b/src/DefaultExtensionMessageFactory.h
@@ -40,6 +40,7 @@
 namespace aria2 {
 
 class BtContext;
+class PeerStorage;
 class Peer;
 class Logger;
 
@@ -47,6 +48,8 @@ class DefaultExtensionMessageFactory:public ExtensionMessageFactory {
 private:
   SharedHandle<BtContext> _btContext;
 
+  SharedHandle<PeerStorage> _peerStorage;
+
   SharedHandle<Peer> _peer;
 
   Logger* _logger;
@@ -64,6 +67,8 @@ public:
 
   void setBtContext(const SharedHandle<BtContext>& btContext);
 
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
+
   void setPeer(const SharedHandle<Peer>& peer);
 };
 
diff --git a/src/DefaultPeerStorage.cc b/src/DefaultPeerStorage.cc
index 3167c1e0..90b9fad0 100644
--- a/src/DefaultPeerStorage.cc
+++ b/src/DefaultPeerStorage.cc
@@ -33,9 +33,11 @@
  */
 /* copyright --> */
 #include "DefaultPeerStorage.h"
+
+#include <algorithm>
+
 #include "LogFactory.h"
 #include "Logger.h"
-#include "BtRegistry.h"
 #include "message.h"
 #include "a2time.h"
 #include "Peer.h"
@@ -44,7 +46,6 @@
 #include "BtSeederStateChoke.h"
 #include "BtLeecherStateChoke.h"
 #include "PieceStorage.h"
-#include <algorithm>
 
 namespace aria2 {
 
@@ -53,7 +54,6 @@ DefaultPeerStorage::DefaultPeerStorage(const BtContextHandle& btContext,
   btContext(btContext),
   option(option),
   logger(LogFactory::getInstance()),
-  btRuntime(BT_RUNTIME(btContext)),
   maxPeerListSize(BtRuntime::MAX_PEERS+(BtRuntime::MAX_PEERS >> 2)),
   removedPeerSessionDownloadLength(0),
   removedPeerSessionUploadLength(0),
@@ -206,7 +206,7 @@ TransferStat DefaultPeerStorage::calculateStat() {
   TransferStat stat = std::for_each(peers.begin(), peers.end(), CalculateStat()).getTransferStat();
   stat.sessionDownloadLength += removedPeerSessionDownloadLength;
   stat.sessionUploadLength += removedPeerSessionUploadLength;
-  stat.setAllTimeUploadLength(btRuntime->getUploadLengthAtStartup()+
+  stat.setAllTimeUploadLength(_btRuntime->getUploadLengthAtStartup()+
 			      stat.getSessionUploadLength());
   return stat;
 }
@@ -252,7 +252,7 @@ void DefaultPeerStorage::returnPeer(const PeerHandle& peer)
 bool DefaultPeerStorage::chokeRoundIntervalElapsed()
 {
   const time_t CHOKE_ROUND_INTERVAL = 10;
-  if(PIECE_STORAGE(btContext)->downloadFinished()) {
+  if(_pieceStorage->downloadFinished()) {
     return _seederStateChoke->getLastRound().elapsed(CHOKE_ROUND_INTERVAL);
   } else {
     return _leecherStateChoke->getLastRound().elapsed(CHOKE_ROUND_INTERVAL);
@@ -263,11 +263,21 @@ void DefaultPeerStorage::executeChoke()
 {
   std::deque<SharedHandle<Peer> > activePeers;
   getActivePeers(activePeers);
-  if(PIECE_STORAGE(btContext)->downloadFinished()) {
+  if(_pieceStorage->downloadFinished()) {
     return _seederStateChoke->executeChoke(activePeers);
   } else {
     return _leecherStateChoke->executeChoke(activePeers);
   }
 }
 
+void DefaultPeerStorage::setPieceStorage(const SharedHandle<PieceStorage>& ps)
+{
+  _pieceStorage = ps;
+}
+
+void DefaultPeerStorage::setBtRuntime(const SharedHandle<BtRuntime>& btRuntime)
+{
+  _btRuntime = btRuntime;
+}
+
 } // namespace aria2
diff --git a/src/DefaultPeerStorage.h b/src/DefaultPeerStorage.h
index b8d6c9bb..228c9144 100644
--- a/src/DefaultPeerStorage.h
+++ b/src/DefaultPeerStorage.h
@@ -45,14 +45,16 @@ class Logger;
 class BtRuntime;
 class BtSeederStateChoke;
 class BtLeecherStateChoke;
+class PieceStorage;
 
 class DefaultPeerStorage : public PeerStorage {
 private:
   SharedHandle<BtContext> btContext;
+  SharedHandle<BtRuntime> _btRuntime;
+  SharedHandle<PieceStorage> _pieceStorage;
   const Option* option;
   std::deque<SharedHandle<Peer> > peers;
   Logger* logger;
-  SharedHandle<BtRuntime> btRuntime;
   size_t maxPeerListSize;
   uint64_t removedPeerSessionDownloadLength;
   uint64_t removedPeerSessionUploadLength;
@@ -67,12 +69,6 @@ public:
 
   virtual ~DefaultPeerStorage();
 
-  void setBtRuntime(const SharedHandle<BtRuntime>& btRuntime) {
-    this->btRuntime = btRuntime;
-  }
-
-  SharedHandle<BtRuntime> getBtRuntime() const { return btRuntime; }
-
   virtual bool addPeer(const SharedHandle<Peer>& peer);
 
   size_t countPeer() const;
@@ -107,6 +103,9 @@ public:
 
   void onReturningPeer(const SharedHandle<Peer>& peer);
 
+  void setPieceStorage(const SharedHandle<PieceStorage>& pieceStorage);
+
+  void setBtRuntime(const SharedHandle<BtRuntime>& btRuntime);
 };
 
 } // namespace aria2
diff --git a/src/DownloadEngine.cc b/src/DownloadEngine.cc
index 1ea23f07..1d6247eb 100644
--- a/src/DownloadEngine.cc
+++ b/src/DownloadEngine.cc
@@ -33,6 +33,14 @@
  */
 /* copyright --> */
 #include "DownloadEngine.h"
+
+#include <signal.h>
+
+#include <cstring>
+#include <cerrno>
+#include <algorithm>
+#include <numeric>
+
 #ifdef ENABLE_ASYNC_DNS
 #include "AsyncNameResolver.h"
 #endif // ENABLE_ASYNC_DNS
@@ -54,11 +62,14 @@
 #include "ServerStatMan.h"
 #include "CookieStorage.h"
 #include "A2STR.h"
-#include <signal.h>
-#include <cstring>
-#include <algorithm>
-#include <numeric>
-#include <cerrno>
+
+#include "BtRegistry.h"
+#include "BtContext.h"
+#include "PeerStorage.h"
+#include "PieceStorage.h"
+#include "BtAnnounce.h"
+#include "BtRuntime.h"
+#include "BtProgressInfoFile.h"
 
 namespace aria2 {
 
@@ -399,7 +410,8 @@ void AsyncNameResolverEntry::process(fd_set* rfdsPtr, fd_set* wfdsPtr)
 DownloadEngine::DownloadEngine():logger(LogFactory::getInstance()),
 				 _haltRequested(false),
 				 _noWait(false),
-				 _cookieStorage(new CookieStorage())
+				 _cookieStorage(new CookieStorage()),
+				 _btRegistry(new BtRegistry())
 {
 #ifdef HAVE_EPOLL
 
@@ -1016,6 +1028,11 @@ DownloadEngine::popPooledSocket
   return s;
 }
 
+SharedHandle<BtRegistry> DownloadEngine::getBtRegistry() const
+{
+  return _btRegistry;
+}
+
 DownloadEngine::SocketPoolEntry::SocketPoolEntry
 (const SharedHandle<SocketCore>& socket,
  const std::map<std::string, std::string>& options,
diff --git a/src/DownloadEngine.h b/src/DownloadEngine.h
index 8a20493e..21421e22 100644
--- a/src/DownloadEngine.h
+++ b/src/DownloadEngine.h
@@ -36,6 +36,15 @@
 #define _D_DOWNLOAD_ENGINE_H_
 
 #include "common.h"
+
+#ifdef HAVE_EPOLL_CREATE
+# include <sys/epoll.h>
+#endif // HAVE_EPOLL_CREATE
+
+#include <string>
+#include <deque>
+#include <map>
+
 #include "SharedHandle.h"
 #include "Command.h"
 #include "a2netcompat.h"
@@ -44,12 +53,6 @@
 #ifdef ENABLE_ASYNC_DNS
 # include "AsyncNameResolver.h"
 #endif // ENABLE_ASYNC_DNS
-#include <string>
-#include <deque>
-#include <map>
-#ifdef HAVE_EPOLL
-# include <sys/epoll.h>
-#endif // HAVE_EPOLL
 
 namespace aria2 {
 
@@ -61,6 +64,7 @@ class StatCalc;
 class CheckIntegrityMan;
 class SocketCore;
 class CookieStorage;
+class BtRegistry;
 
 class CommandEvent
 {
@@ -292,6 +296,8 @@ private:
 
   SharedHandle<CookieStorage> _cookieStorage;
 
+  SharedHandle<BtRegistry> _btRegistry;
+
   void shortSleep() const;
 
   /**
@@ -405,6 +411,8 @@ public:
    uint16_t port);
 
   SharedHandle<CookieStorage> getCookieStorage() const;
+
+  SharedHandle<BtRegistry> getBtRegistry() const;
 };
 
 typedef SharedHandle<DownloadEngine> DownloadEngineHandle;
diff --git a/src/InitiatorMSEHandshakeCommand.cc b/src/InitiatorMSEHandshakeCommand.cc
index eb3511aa..00174d2a 100644
--- a/src/InitiatorMSEHandshakeCommand.cc
+++ b/src/InitiatorMSEHandshakeCommand.cc
@@ -46,10 +46,8 @@
 #include "PeerConnection.h"
 #include "BtContext.h"
 #include "BtRuntime.h"
-#include "PieceStorage.h"
 #include "PeerStorage.h"
-#include "BtAnnounce.h"
-#include "BtProgressInfoFile.h"
+#include "PieceStorage.h"
 #include "Option.h"
 #include "MSEHandshake.h"
 #include "ARC4Encryptor.h"
@@ -63,11 +61,13 @@ InitiatorMSEHandshakeCommand::InitiatorMSEHandshakeCommand
  const SharedHandle<Peer>& p,
  DownloadEngine* e,
  const SharedHandle<BtContext>& btContext,
+ const SharedHandle<BtRuntime>& btRuntime,
  const SharedHandle<SocketCore>& s):
 
   PeerAbstractCommand(cuid, p, e, s),
-  BtContextAwareCommand(btContext),
   RequestGroupAware(requestGroup),
+  _btContext(btContext),
+  _btRuntime(btRuntime),
   _sequence(INITIATOR_SEND_KEY),
   _mseHandshake(new MSEHandshake(cuid, socket, e->option))
 {
@@ -75,12 +75,12 @@ InitiatorMSEHandshakeCommand::InitiatorMSEHandshakeCommand
   setWriteCheckSocket(socket);
   setTimeout(e->option->getAsInt(PREF_PEER_CONNECTION_TIMEOUT));
 
-  btRuntime->increaseConnections();
+  _btRuntime->increaseConnections();
 }
 
 InitiatorMSEHandshakeCommand::~InitiatorMSEHandshakeCommand()
 {
-  btRuntime->decreaseConnections();
+  _btRuntime->decreaseConnections();
   
   delete _mseHandshake;
 }
@@ -112,7 +112,7 @@ bool InitiatorMSEHandshakeCommand::executeInternal() {
     break;
   case INITIATOR_WAIT_KEY: {
     if(_mseHandshake->receivePublicKey()) {
-      _mseHandshake->initCipher(btContext->getInfoHash());
+      _mseHandshake->initCipher(_btContext->getInfoHash());
       if(_mseHandshake->sendInitiatorStep2()) {
 	_sequence = INITIATOR_FIND_VC_MARKER;
       } else {
@@ -148,11 +148,13 @@ bool InitiatorMSEHandshakeCommand::executeInternal() {
 	peerConnection->enableEncryption(_mseHandshake->getEncryptor(),
 					 _mseHandshake->getDecryptor());
       }
-      Command* c =
-	  new PeerInteractionCommand(cuid, _requestGroup, peer, e, btContext,
+      PeerInteractionCommand* c =
+	  new PeerInteractionCommand(cuid, _requestGroup, peer, e, _btContext,
+				     _btRuntime, _pieceStorage,
 				     socket,
 				     PeerInteractionCommand::INITIATOR_SEND_HANDSHAKE,
 				     peerConnection);
+      c->setPeerStorage(_peerStorage);
       e->commands.push_back(c);
       return true;
     }
@@ -167,21 +169,25 @@ bool InitiatorMSEHandshakeCommand::prepareForNextPeer(time_t wait)
 {
   if(e->option->getAsBool(PREF_BT_REQUIRE_CRYPTO)) {
     logger->info("CUID#%d - Establishing connection using legacy BitTorrent handshake is disabled by preference.", cuid);
-    if(peerStorage->isPeerAvailable() && btRuntime->lessThanEqMinPeers()) {
-      SharedHandle<Peer> peer = peerStorage->getUnusedPeer();
+    if(_peerStorage->isPeerAvailable() && _btRuntime->lessThanEqMinPeers()) {
+      SharedHandle<Peer> peer = _peerStorage->getUnusedPeer();
       peer->usedBy(CUIDCounterSingletonHolder::instance()->newID());
-      Command* command =
-	new PeerInitiateConnectionCommand(peer->usedBy(), _requestGroup, peer, e,
-					  btContext);
+      PeerInitiateConnectionCommand* command =
+	new PeerInitiateConnectionCommand(peer->usedBy(), _requestGroup, peer,
+					  e, _btContext, _btRuntime);
+      command->setPeerStorage(_peerStorage);
+      command->setPieceStorage(_pieceStorage);
       e->commands.push_back(command);
     }
     return true;
   } else {
     // try legacy BitTorrent handshake
     logger->info("CUID#%d - Retry using legacy BitTorrent handshake.", cuid);
-    Command* command =
-      new PeerInitiateConnectionCommand(cuid, _requestGroup, peer, e, btContext,
-					false);
+    PeerInitiateConnectionCommand* command =
+      new PeerInitiateConnectionCommand(cuid, _requestGroup, peer, e,
+					_btContext, _btRuntime, false);
+    command->setPeerStorage(_peerStorage);
+    command->setPieceStorage(_pieceStorage);
     e->commands.push_back(command);
     return true;
   }
@@ -190,13 +196,25 @@ bool InitiatorMSEHandshakeCommand::prepareForNextPeer(time_t wait)
 void InitiatorMSEHandshakeCommand::onAbort()
 {
   if(e->option->getAsBool(PREF_BT_REQUIRE_CRYPTO)) {
-    peerStorage->returnPeer(peer);
+    _peerStorage->returnPeer(peer);
   }
 }
 
 bool InitiatorMSEHandshakeCommand::exitBeforeExecute()
 {
-  return btRuntime->isHalt();
+  return _btRuntime->isHalt();
+}
+
+void InitiatorMSEHandshakeCommand::setPeerStorage
+(const SharedHandle<PeerStorage>& peerStorage)
+{
+  _peerStorage = peerStorage;
+}
+
+void InitiatorMSEHandshakeCommand::setPieceStorage
+(const SharedHandle<PieceStorage>& pieceStorage)
+{
+  _pieceStorage = pieceStorage;
 }
 
 } // namespace aria2
diff --git a/src/InitiatorMSEHandshakeCommand.h b/src/InitiatorMSEHandshakeCommand.h
index a9304d6d..4db8dd4a 100644
--- a/src/InitiatorMSEHandshakeCommand.h
+++ b/src/InitiatorMSEHandshakeCommand.h
@@ -37,14 +37,16 @@
 
 #include "PeerAbstractCommand.h"
 #include "RequestGroupAware.h"
-#include "BtContextAwareCommand.h"
 
 namespace aria2 {
 
+class BtContext;
+class PeerStorage;
+class PieceStorage;
+class BtRuntime;
 class MSEHandshake;
 
 class InitiatorMSEHandshakeCommand : public PeerAbstractCommand,
-				     public BtContextAwareCommand,
 				     public RequestGroupAware
 {
 public:
@@ -58,6 +60,14 @@ public:
     INITIATOR_RECEIVE_PAD_D,
   };
 private:
+  SharedHandle<BtContext> _btContext;
+
+  SharedHandle<PeerStorage> _peerStorage;
+
+  SharedHandle<PieceStorage> _pieceStorage;
+
+  SharedHandle<BtRuntime> _btRuntime;
+
   Seq _sequence;
   MSEHandshake* _mseHandshake;
 protected:
@@ -71,10 +81,14 @@ public:
 			       const SharedHandle<Peer>& peer,
 			       DownloadEngine* e,
 			       const SharedHandle<BtContext>& btContext,
+			       const SharedHandle<BtRuntime>& btRuntime,
 			       const SharedHandle<SocketCore>& s);
 
   virtual ~InitiatorMSEHandshakeCommand();
 
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
+
+  void setPieceStorage(const SharedHandle<PieceStorage>& pieceStorage);
 };
 
 } // namespace aria2
diff --git a/src/MSEHandshake.cc b/src/MSEHandshake.cc
index 3cee3ef1..7eed5928 100644
--- a/src/MSEHandshake.cc
+++ b/src/MSEHandshake.cc
@@ -33,6 +33,10 @@
  */
 /* copyright --> */
 #include "MSEHandshake.h"
+
+#include <cstring>
+#include <cassert>
+
 #include "message.h"
 #include "DlAbortEx.h"
 #include "LogFactory.h"
@@ -46,13 +50,10 @@
 #include "MessageDigestHelper.h"
 #include "SimpleRandomizer.h"
 #include "Util.h"
-#include "BtRegistry.h"
 #include "BtContext.h"
 #include "prefs.h"
 #include "Option.h"
 #include "StringFormat.h"
-#include <cstring>
-#include <cassert>
 
 namespace aria2 {
 
@@ -424,14 +425,14 @@ bool MSEHandshake::findReceiverHashMarker()
   return true;
 }
 
-bool MSEHandshake::receiveReceiverHashAndPadCLength()
+bool MSEHandshake::receiveReceiverHashAndPadCLength
+(const std::deque<SharedHandle<BtContext> >& btContexts)
 {
   size_t r = 20+VC_LENGTH+CRYPTO_BITFIELD_LENGTH+2/*PadC length*/-_rbufLength;
   if(r > receiveNBytes(r)) {
     return false;
   }
   // resolve info hash
-  std::deque<SharedHandle<BtContext> > btContexts = BtRegistry::getAllBtContext();
   // pointing to the position of HASH('req2', SKEY) xor HASH('req3', S)
   unsigned char* rbufptr = _rbuf;
   SharedHandle<BtContext> btContext;
diff --git a/src/MSEHandshake.h b/src/MSEHandshake.h
index 5b381c9f..6d4817f8 100644
--- a/src/MSEHandshake.h
+++ b/src/MSEHandshake.h
@@ -36,6 +36,9 @@
 #define _D_MSE_HANDSHAKE_H_
 
 #include "common.h"
+
+#include <deque>
+
 #include "SharedHandle.h"
 #include "BtConstants.h"
 #include "SocketBuffer.h"
@@ -48,6 +51,7 @@ class SocketCore;
 class DHKeyExchange;
 class ARC4Encryptor;
 class ARC4Decryptor;
+class BtContext;
 
 class MSEHandshake {
 public:
@@ -153,7 +157,8 @@ public:
 
   bool findReceiverHashMarker();
 
-  bool receiveReceiverHashAndPadCLength();
+  bool receiveReceiverHashAndPadCLength
+  (const std::deque<SharedHandle<BtContext> >& btContexts);
 
   bool receiveReceiverIALength();
 
diff --git a/src/Makefile.am b/src/Makefile.am
index 221ccbd3..cd8d3b59 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -252,7 +252,6 @@ SRCS += MetaEntry.h\
 	BtAnnounce.cc BtAnnounce.h\
 	DefaultBtAnnounce.cc DefaultBtAnnounce.h\
 	BtRuntime.h\
-	BtContextAwareCommand.cc BtContextAwareCommand.h\
 	BtMessage.h\
 	AbstractBtMessage.cc AbstractBtMessage.h\
 	SimpleBtMessage.cc SimpleBtMessage.h\
diff --git a/src/Makefile.in b/src/Makefile.in
index 258fdb97..83360def 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -81,7 +81,6 @@ bin_PROGRAMS = aria2c$(EXEEXT)
 @ENABLE_BITTORRENT_TRUE@	BtAnnounce.cc BtAnnounce.h\
 @ENABLE_BITTORRENT_TRUE@	DefaultBtAnnounce.cc DefaultBtAnnounce.h\
 @ENABLE_BITTORRENT_TRUE@	BtRuntime.h\
-@ENABLE_BITTORRENT_TRUE@	BtContextAwareCommand.cc BtContextAwareCommand.h\
 @ENABLE_BITTORRENT_TRUE@	BtMessage.h\
 @ENABLE_BITTORRENT_TRUE@	AbstractBtMessage.cc AbstractBtMessage.h\
 @ENABLE_BITTORRENT_TRUE@	SimpleBtMessage.cc SimpleBtMessage.h\
@@ -446,9 +445,8 @@ am__libaria2c_a_SOURCES_DIST = Socket.h SocketCore.cc SocketCore.h \
 	DefaultBtContext.h PeerStorage.h DefaultPeerStorage.cc \
 	DefaultPeerStorage.h BtAnnounce.cc BtAnnounce.h \
 	DefaultBtAnnounce.cc DefaultBtAnnounce.h BtRuntime.h \
-	BtContextAwareCommand.cc BtContextAwareCommand.h BtMessage.h \
-	AbstractBtMessage.cc AbstractBtMessage.h SimpleBtMessage.cc \
-	SimpleBtMessage.h BtAllowedFastMessage.cc \
+	BtMessage.h AbstractBtMessage.cc AbstractBtMessage.h \
+	SimpleBtMessage.cc SimpleBtMessage.h BtAllowedFastMessage.cc \
 	BtAllowedFastMessage.h BtBitfieldMessage.cc \
 	BtBitfieldMessage.h BtCancelMessage.cc BtCancelMessage.h \
 	BtChokeMessage.cc BtChokeMessage.h BtHaveAllMessage.cc \
@@ -608,7 +606,6 @@ am__libaria2c_a_SOURCES_DIST = Socket.h SocketCore.cc SocketCore.h \
 @ENABLE_BITTORRENT_TRUE@	DefaultPeerStorage.$(OBJEXT) \
 @ENABLE_BITTORRENT_TRUE@	BtAnnounce.$(OBJEXT) \
 @ENABLE_BITTORRENT_TRUE@	DefaultBtAnnounce.$(OBJEXT) \
-@ENABLE_BITTORRENT_TRUE@	BtContextAwareCommand.$(OBJEXT) \
 @ENABLE_BITTORRENT_TRUE@	AbstractBtMessage.$(OBJEXT) \
 @ENABLE_BITTORRENT_TRUE@	SimpleBtMessage.$(OBJEXT) \
 @ENABLE_BITTORRENT_TRUE@	BtAllowedFastMessage.$(OBJEXT) \
@@ -1261,7 +1258,6 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/BtCheckIntegrityEntry.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/BtChokeMessage.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/BtContext.Po@am__quote@
-@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/BtContextAwareCommand.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/BtDependency.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/BtExtendedMessage.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/BtFileAllocationEntry.Po@am__quote@
diff --git a/src/PeerChokeCommand.cc b/src/PeerChokeCommand.cc
index d9205805..8799605f 100644
--- a/src/PeerChokeCommand.cc
+++ b/src/PeerChokeCommand.cc
@@ -42,23 +42,34 @@ namespace aria2 {
 
 PeerChokeCommand::PeerChokeCommand(int32_t cuid,
 				   DownloadEngine* e,
-				   const BtContextHandle& btContext):
+				   const SharedHandle<BtContext>& btContext):
   Command(cuid),
-  BtContextAwareCommand(btContext),
-  e(e)
-{}
+  e(e),
+  _btContext(btContext) {}
 
 PeerChokeCommand::~PeerChokeCommand() {}
 
 bool PeerChokeCommand::execute() {
-  if(btRuntime->isHalt()) {
+  if(_btRuntime->isHalt()) {
     return true;
   }
-  if(peerStorage->chokeRoundIntervalElapsed()) {
-    peerStorage->executeChoke();
+  if(_peerStorage->chokeRoundIntervalElapsed()) {
+    _peerStorage->executeChoke();
   }
   e->commands.push_back(this);
   return false;
 }
 
+void PeerChokeCommand::setBtRuntime
+(const SharedHandle<BtRuntime>& btRuntime)
+{
+  _btRuntime = btRuntime;
+}
+
+void PeerChokeCommand::setPeerStorage
+(const SharedHandle<PeerStorage>& peerStorage)
+{
+  _peerStorage = peerStorage;
+}
+
 } // namespace aria2
diff --git a/src/PeerChokeCommand.h b/src/PeerChokeCommand.h
index 23bb8764..b81781f3 100644
--- a/src/PeerChokeCommand.h
+++ b/src/PeerChokeCommand.h
@@ -36,18 +36,24 @@
 #define _D_PEER_CHOKE_COMMAND_H_
 
 #include "Command.h"
-#include "BtContextAwareCommand.h"
+#include "SharedHandle.h"
 
 namespace aria2 {
 
 class DownloadEngine;
+class BtContext;
+class BtRuntime;
+class PeerStorage;
 
-class PeerChokeCommand : public Command,
-			 public BtContextAwareCommand
-{
+class PeerChokeCommand : public Command {
 private:
   DownloadEngine* e;
 
+  SharedHandle<BtContext> _btContext;
+
+  SharedHandle<PeerStorage> _peerStorage;
+
+  SharedHandle<BtRuntime> _btRuntime;
 public:
   PeerChokeCommand(int32_t cuid,
 		   DownloadEngine* e,
@@ -56,6 +62,10 @@ public:
   virtual ~PeerChokeCommand();
 
   virtual bool execute();
+
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
+
+  void setBtRuntime(const SharedHandle<BtRuntime>& btRuntime);
 };
 
 } // namespace aria2
diff --git a/src/PeerInitiateConnectionCommand.cc b/src/PeerInitiateConnectionCommand.cc
index a9570250..1c74eba5 100644
--- a/src/PeerInitiateConnectionCommand.cc
+++ b/src/PeerInitiateConnectionCommand.cc
@@ -43,33 +43,35 @@
 #include "Socket.h"
 #include "Logger.h"
 #include "Peer.h"
-#include "PeerConnection.h"
 #include "BtContext.h"
 #include "BtRuntime.h"
-#include "PieceStorage.h"
 #include "PeerStorage.h"
-#include "BtAnnounce.h"
-#include "BtProgressInfoFile.h"
+#include "PieceStorage.h"
+#include "PeerConnection.h"
 
 namespace aria2 {
 
-PeerInitiateConnectionCommand::PeerInitiateConnectionCommand(int cuid,
-							     RequestGroup* requestGroup,
-							     const PeerHandle& peer,
-							     DownloadEngine* e,
-							     const BtContextHandle& btContext,
-							     bool mseHandshakeEnabled)
-  :PeerAbstractCommand(cuid, peer, e),
-   BtContextAwareCommand(btContext),
-   RequestGroupAware(requestGroup),
-   _mseHandshakeEnabled(mseHandshakeEnabled)
+PeerInitiateConnectionCommand::PeerInitiateConnectionCommand
+(int cuid,
+ RequestGroup* requestGroup,
+ const PeerHandle& peer,
+ DownloadEngine* e,
+ const SharedHandle<BtContext>& btContext,
+ const SharedHandle<BtRuntime>& btRuntime,
+ bool mseHandshakeEnabled)
+  :
+  PeerAbstractCommand(cuid, peer, e),
+  RequestGroupAware(requestGroup),
+  _btContext(btContext),
+  _btRuntime(btRuntime),
+  _mseHandshakeEnabled(mseHandshakeEnabled)
 {
-  btRuntime->increaseConnections();
+  _btRuntime->increaseConnections();
 }
 
 PeerInitiateConnectionCommand::~PeerInitiateConnectionCommand()
 {
-  btRuntime->decreaseConnections();
+  _btRuntime->decreaseConnections();
 }
 
 bool PeerInitiateConnectionCommand::executeInternal() {
@@ -77,40 +79,58 @@ bool PeerInitiateConnectionCommand::executeInternal() {
 	       peer->port);
   socket.reset(new SocketCore());
   socket->establishConnection(peer->ipaddr, peer->port);
-  Command* command;
   if(_mseHandshakeEnabled) {
-    command =
-      new InitiatorMSEHandshakeCommand(cuid, _requestGroup, peer, e, btContext,
-				       socket);
+    InitiatorMSEHandshakeCommand* c =
+      new InitiatorMSEHandshakeCommand(cuid, _requestGroup, peer, e, _btContext,
+				       _btRuntime, socket);
+    c->setPeerStorage(_peerStorage);
+    c->setPieceStorage(_pieceStorage);
+    e->commands.push_back(c);
   } else {
-    command =
-      new PeerInteractionCommand(cuid, _requestGroup, peer, e, btContext, socket,
-				 PeerInteractionCommand::INITIATOR_SEND_HANDSHAKE);
+    PeerInteractionCommand* command =
+      new PeerInteractionCommand
+      (cuid, _requestGroup, peer, e, _btContext, _btRuntime, _pieceStorage,
+       socket, PeerInteractionCommand::INITIATOR_SEND_HANDSHAKE);
+    command->setPeerStorage(_peerStorage);
+    e->commands.push_back(command);
   }
-  e->commands.push_back(command);
   return true;
 }
 
 // TODO this method removed when PeerBalancerCommand is implemented
 bool PeerInitiateConnectionCommand::prepareForNextPeer(time_t wait) {
-  if(peerStorage->isPeerAvailable() && btRuntime->lessThanEqMinPeers()) {
-    PeerHandle peer = peerStorage->getUnusedPeer();
+  if(_peerStorage->isPeerAvailable() && _btRuntime->lessThanEqMinPeers()) {
+    PeerHandle peer = _peerStorage->getUnusedPeer();
     peer->usedBy(CUIDCounterSingletonHolder::instance()->newID());
-    Command* command =
+    PeerInitiateConnectionCommand* command =
       new PeerInitiateConnectionCommand(peer->usedBy(), _requestGroup, peer, e,
-					btContext);
+					_btContext, _btRuntime);
+    command->setPeerStorage(_peerStorage);
+    command->setPieceStorage(_pieceStorage);
     e->commands.push_back(command);
   }
   return true;
 }
 
 void PeerInitiateConnectionCommand::onAbort() {
-  peerStorage->returnPeer(peer);
+  _peerStorage->returnPeer(peer);
 }
 
 bool PeerInitiateConnectionCommand::exitBeforeExecute()
 {
-  return btRuntime->isHalt();
+  return _btRuntime->isHalt();
+}
+
+void PeerInitiateConnectionCommand::setPeerStorage
+(const SharedHandle<PeerStorage>& peerStorage)
+{
+  _peerStorage = peerStorage;
+}
+
+void PeerInitiateConnectionCommand::setPieceStorage
+(const SharedHandle<PieceStorage>& pieceStorage)
+{
+  _pieceStorage = pieceStorage;
 }
 
 } // namespace aria2
diff --git a/src/PeerInitiateConnectionCommand.h b/src/PeerInitiateConnectionCommand.h
index 04b58cc1..7a1eced0 100644
--- a/src/PeerInitiateConnectionCommand.h
+++ b/src/PeerInitiateConnectionCommand.h
@@ -37,15 +37,26 @@
 
 #include "PeerAbstractCommand.h"
 #include "RequestGroupAware.h"
-#include "BtContextAwareCommand.h"
 
 namespace aria2 {
 
+class BtContext;
+class BtRuntime;
+class PeerStorage;
+class PieceStorage;
+
 class PeerInitiateConnectionCommand : public PeerAbstractCommand,
-				      public BtContextAwareCommand,
 				      public RequestGroupAware
 {
 private:
+  SharedHandle<BtContext> _btContext;
+
+  SharedHandle<BtRuntime> _btRuntime;
+
+  SharedHandle<PeerStorage> _peerStorage;
+
+  SharedHandle<PieceStorage> _pieceStorage;
+
   bool _mseHandshakeEnabled;
 protected:
   virtual bool executeInternal();
@@ -59,9 +70,14 @@ public:
 				const SharedHandle<Peer>& peer,
 				DownloadEngine* e,
 				const SharedHandle<BtContext>& btContext,
+				const SharedHandle<BtRuntime>& btRuntime,
 				bool mseHandshakeEnabled = true);
 
   virtual ~PeerInitiateConnectionCommand();
+
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
+
+  void setPieceStorage(const SharedHandle<PieceStorage>& pieceStorage);
 };
 
 } // namespace aria2
diff --git a/src/PeerInteractionCommand.cc b/src/PeerInteractionCommand.cc
index a0324371..50d9c7e8 100644
--- a/src/PeerInteractionCommand.cc
+++ b/src/PeerInteractionCommand.cc
@@ -33,6 +33,9 @@
  */
 /* copyright --> */
 #include "PeerInteractionCommand.h"
+
+#include <algorithm>
+
 #include "DownloadEngine.h"
 #include "PeerInitiateConnectionCommand.h"
 #include "DefaultBtInteractive.h"
@@ -43,7 +46,6 @@
 #include "Option.h"
 #include "BtContext.h"
 #include "BtRegistry.h"
-#include "PeerObject.h"
 #include "Peer.h"
 #include "BtMessage.h"
 #include "BtRuntime.h"
@@ -64,21 +66,28 @@
 #include "DHTRegistry.h"
 #include "PieceStorage.h"
 #include "RequestGroup.h"
-#include <algorithm>
+#include "BtAnnounce.h"
+#include "BtProgressInfoFile.h"
+#include "DefaultExtensionMessageFactory.h"
 
 namespace aria2 {
 
-PeerInteractionCommand::PeerInteractionCommand(int32_t cuid,
-					       RequestGroup* requestGroup,
-					       const PeerHandle& p,
-					       DownloadEngine* e,
-					       const BtContextHandle& btContext,
-					       const SocketHandle& s,
-					       Seq sequence,
-					       const PeerConnectionHandle& passedPeerConnection)
+PeerInteractionCommand::PeerInteractionCommand
+(int32_t cuid,
+ RequestGroup* requestGroup,
+ const PeerHandle& p,
+ DownloadEngine* e,
+ const SharedHandle<BtContext>& btContext,
+ const SharedHandle<BtRuntime>& btRuntime,
+ const SharedHandle<PieceStorage>& pieceStorage,
+ const SocketHandle& s,
+ Seq sequence,
+ const PeerConnectionHandle& passedPeerConnection)
   :PeerAbstractCommand(cuid, p, e, s),
-   BtContextAwareCommand(btContext),
    RequestGroupAware(requestGroup),
+   _btContext(btContext),
+   _btRuntime(btRuntime),
+   _pieceStorage(pieceStorage),
    sequence(sequence),
    maxDownloadSpeedLimit(0)
 {
@@ -88,9 +97,21 @@ PeerInteractionCommand::PeerInteractionCommand(int32_t cuid,
     setWriteCheckSocket(socket);
     setTimeout(e->option->getAsInt(PREF_PEER_CONNECTION_TIMEOUT));
   }
-  DefaultBtMessageFactoryHandle factory(new DefaultBtMessageFactory());
+
+  SharedHandle<BtRegistry> btRegistry = e->getBtRegistry();
+  SharedHandle<PeerStorage> peerStorage =
+    btRegistry->getPeerStorage(_btContext->getInfoHashAsString());
+
+  SharedHandle<DefaultExtensionMessageFactory> extensionMessageFactory
+    (new DefaultExtensionMessageFactory(_btContext, peer));
+  extensionMessageFactory->setPeerStorage(peerStorage);
+
+  SharedHandle<DefaultBtMessageFactory> factory(new DefaultBtMessageFactory());
   factory->setCuid(cuid);
-  factory->setBtContext(btContext);
+  factory->setBtContext(_btContext);
+  factory->setPieceStorage(pieceStorage);
+  factory->setPeerStorage(peerStorage);
+  factory->setExtensionMessageFactory(extensionMessageFactory);
   factory->setPeer(peer);
   factory->setLocalNode(DHTRegistry::_localNode);
   factory->setRoutingTable(DHTRegistry::_routingTable);
@@ -104,39 +125,52 @@ PeerInteractionCommand::PeerInteractionCommand(int32_t cuid,
     peerConnection = passedPeerConnection;
   }
 
-  DefaultBtMessageDispatcherHandle dispatcher(new DefaultBtMessageDispatcher());
+  SharedHandle<DefaultBtMessageDispatcher> dispatcher
+    (new DefaultBtMessageDispatcher());
   dispatcher->setCuid(cuid);
   dispatcher->setPeer(peer);
-  dispatcher->setBtContext(btContext);
-  dispatcher->setMaxUploadSpeedLimit(e->option->getAsInt(PREF_MAX_UPLOAD_LIMIT));
+  dispatcher->setBtContext(_btContext);
+  dispatcher->setPieceStorage(pieceStorage);
+  dispatcher->setPeerStorage(peerStorage);
+  dispatcher->setMaxUploadSpeedLimit
+    (e->option->getAsInt(PREF_MAX_UPLOAD_LIMIT));
   dispatcher->setRequestTimeout(e->option->getAsInt(PREF_BT_REQUEST_TIMEOUT));
   dispatcher->setBtMessageFactory(factory);
 
   DefaultBtMessageReceiverHandle receiver(new DefaultBtMessageReceiver());
   receiver->setCuid(cuid);
   receiver->setPeer(peer);
-  receiver->setBtContext(btContext);
+  receiver->setBtContext(_btContext);
   receiver->setPeerConnection(peerConnection);
   receiver->setDispatcher(dispatcher);
   receiver->setBtMessageFactory(factory);
 
-  DefaultBtRequestFactoryHandle reqFactory(new DefaultBtRequestFactory());
+  SharedHandle<DefaultBtRequestFactory> reqFactory
+    (new DefaultBtRequestFactory());
   reqFactory->setCuid(cuid);
   reqFactory->setPeer(peer);
-  reqFactory->setBtContext(btContext);
+  reqFactory->setBtContext(_btContext);
+  reqFactory->setPieceStorage(pieceStorage);
   reqFactory->setBtMessageDispatcher(dispatcher);
   reqFactory->setBtMessageFactory(factory);
 
-  DefaultBtInteractiveHandle btInteractive(new DefaultBtInteractive(btContext, peer));
+  DefaultBtInteractiveHandle btInteractive
+    (new DefaultBtInteractive(_btContext, peer));
+  btInteractive->setBtRuntime(_btRuntime);
+  btInteractive->setPieceStorage(_pieceStorage);
+  btInteractive->setPeerStorage(peerStorage); // Note: Not a member variable.
   btInteractive->setCuid(cuid);
   btInteractive->setBtMessageReceiver(receiver);
   btInteractive->setDispatcher(dispatcher);
   btInteractive->setBtRequestFactory(reqFactory);
   btInteractive->setPeerConnection(peerConnection);
-  btInteractive->setKeepAliveInterval(e->option->getAsInt(PREF_BT_KEEP_ALIVE_INTERVAL));
-  btInteractive->setMaxDownloadSpeedLimit(e->option->getAsInt(PREF_MAX_DOWNLOAD_LIMIT));
+  btInteractive->setExtensionMessageFactory(extensionMessageFactory);
+  btInteractive->setKeepAliveInterval
+    (e->option->getAsInt(PREF_BT_KEEP_ALIVE_INTERVAL));
+  btInteractive->setMaxDownloadSpeedLimit
+    (e->option->getAsInt(PREF_MAX_DOWNLOAD_LIMIT));
   btInteractive->setBtMessageFactory(factory);
-  if(!btContext->isPrivate()) {
+  if(!_btContext->isPrivate()) {
     if(e->option->getAsBool(PREF_ENABLE_PEER_EXCHANGE)) {
       btInteractive->setUTPexEnabled(true);
     }
@@ -153,32 +187,23 @@ PeerInteractionCommand::PeerInteractionCommand(int32_t cuid,
   factory->setBtRequestFactory(reqFactory);
   factory->setPeerConnection(peerConnection);
 
-  PeerObjectHandle peerObject(new PeerObject());
-  peerObject->btMessageDispatcher = dispatcher;
-  peerObject->btMessageReceiver = receiver;
-  peerObject->btMessageFactory = factory;
-  peerObject->btRequestFactory = reqFactory;
-  peerObject->peerConnection = peerConnection;
-  
-  PEER_OBJECT_CLUSTER(btContext)->registerHandle(peer->getID(), peerObject);
-
   setUploadLimit(e->option->getAsInt(PREF_MAX_UPLOAD_LIMIT));
-  peer->allocateSessionResource(btContext->getPieceLength(), btContext->getTotalLength());
+  peer->allocateSessionResource(_btContext->getPieceLength(),
+				_btContext->getTotalLength());
 
   maxDownloadSpeedLimit = e->option->getAsInt(PREF_MAX_DOWNLOAD_LIMIT);
 
-  btRuntime->increaseConnections();
+  _btRuntime->increaseConnections();
 }
 
 PeerInteractionCommand::~PeerInteractionCommand() {
   if(peer->getCompletedLength() > 0) {
-    pieceStorage->subtractPieceStats(peer->getBitfield(),
-				     peer->getBitfieldLength());
+    _pieceStorage->subtractPieceStats(peer->getBitfield(),
+				      peer->getBitfieldLength());
   }
   peer->releaseSessionResource();
-  PEER_OBJECT_CLUSTER(btContext)->unregisterHandle(peer->getID());
 					
-  btRuntime->decreaseConnections();
+  _btRuntime->decreaseConnections();
   //logger->debug("CUID#%d - unregistered message factory using ID:%s",
   //cuid, peer->getId().c_str());
 }
@@ -229,7 +254,8 @@ bool PeerInteractionCommand::executeInternal() {
     if(btInteractive->countReceivedMessageInIteration() > 0) {
       updateKeepAlive();
     }
-    if((peer->amInterested() && !peer->peerChoking() && (peer->getLatency() < 1500)) ||
+    if((peer->amInterested() && !peer->peerChoking() &&
+	(peer->getLatency() < 1500)) ||
        (peer->peerInterested() && !peer->amChoking())) {
 
       // Writable check causes CPU usage high because socket becomes writable
@@ -263,15 +289,18 @@ bool PeerInteractionCommand::executeInternal() {
 
 // TODO this method removed when PeerBalancerCommand is implemented
 bool PeerInteractionCommand::prepareForNextPeer(time_t wait) {
-  if(peerStorage->isPeerAvailable() && btRuntime->lessThanEqMinPeers()) {
-    PeerHandle peer = peerStorage->getUnusedPeer();
+  if(_peerStorage->isPeerAvailable() && _btRuntime->lessThanEqMinPeers()) {
+    PeerHandle peer = _peerStorage->getUnusedPeer();
     peer->usedBy(CUIDCounterSingletonHolder::instance()->newID());
     PeerInitiateConnectionCommand* command =
       new PeerInitiateConnectionCommand(peer->usedBy(),
 					_requestGroup,
 					peer,
 					e,
-					btContext);
+					_btContext,
+					_btRuntime);
+    command->setPeerStorage(_peerStorage);
+    command->setPieceStorage(_pieceStorage);
     e->commands.push_back(command);
   }
   return true;
@@ -279,7 +308,7 @@ bool PeerInteractionCommand::prepareForNextPeer(time_t wait) {
 
 void PeerInteractionCommand::onAbort() {
   btInteractive->cancelAllPiece();
-  peerStorage->returnPeer(peer);
+  _peerStorage->returnPeer(peer);
 }
 
 void PeerInteractionCommand::onFailure()
@@ -289,7 +318,13 @@ void PeerInteractionCommand::onFailure()
 
 bool PeerInteractionCommand::exitBeforeExecute()
 {
-  return btRuntime->isHalt();
+  return _btRuntime->isHalt();
+}
+
+void PeerInteractionCommand::setPeerStorage
+(const SharedHandle<PeerStorage>& peerStorage)
+{
+  _peerStorage = peerStorage;
 }
 
 } // namespace aria2
diff --git a/src/PeerInteractionCommand.h b/src/PeerInteractionCommand.h
index b6533062..4e793484 100644
--- a/src/PeerInteractionCommand.h
+++ b/src/PeerInteractionCommand.h
@@ -37,15 +37,17 @@
 
 #include "PeerAbstractCommand.h"
 #include "RequestGroupAware.h"
-#include "BtContextAwareCommand.h"
 
 namespace aria2 {
 
+class BtContext;
 class BtInteractive;
 class PeerConnection;
+class BtRuntime;
+class PeerStorage;
+class PieceStorage;
 
 class PeerInteractionCommand : public PeerAbstractCommand,
-			       public BtContextAwareCommand,
 			       public RequestGroupAware
 {
 public:
@@ -55,6 +57,14 @@ public:
     RECEIVER_WAIT_HANDSHAKE,
     WIRED};
 private:
+  SharedHandle<BtContext> _btContext;
+
+  SharedHandle<BtRuntime> _btRuntime;
+
+  SharedHandle<PieceStorage> _pieceStorage;
+
+  SharedHandle<PeerStorage> _peerStorage;
+
   Seq sequence;
   SharedHandle<BtInteractive> btInteractive;
   unsigned int maxDownloadSpeedLimit;
@@ -70,12 +80,16 @@ public:
 			 const SharedHandle<Peer>& peer,
 			 DownloadEngine* e,
 			 const SharedHandle<BtContext>& btContext,
+			 const SharedHandle<BtRuntime>& btRuntime,
+			 const SharedHandle<PieceStorage>& pieceStorage,
 			 const SharedHandle<SocketCore>& s,
 			 Seq sequence,
-			 const SharedHandle<PeerConnection>& peerConnection = SharedHandle<PeerConnection>());
+			 const SharedHandle<PeerConnection>& peerConnection =
+			 SharedHandle<PeerConnection>());
 
   virtual ~PeerInteractionCommand();
 
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
 };
 
 } // namespace aria2
diff --git a/src/PeerObject.h b/src/PeerObject.h
deleted file mode 100644
index f83f95a5..00000000
--- a/src/PeerObject.h
+++ /dev/null
@@ -1,63 +0,0 @@
-/* <!-- copyright */
-/*
- * aria2 - The high speed download utility
- *
- * Copyright (C) 2006 Tatsuhiro Tsujikawa
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
- *
- * In addition, as a special exception, the copyright holders give
- * permission to link the code of portions of this program with the
- * OpenSSL library under certain conditions as described in each
- * individual source file, and distribute linked combinations
- * including the two.
- * You must obey the GNU General Public License in all respects
- * for all of the code used other than OpenSSL.  If you modify
- * file(s) with this exception, you may extend this exception to your
- * version of the file(s), but you are not obligated to do so.  If you
- * do not wish to do so, delete this exception statement from your
- * version.  If you delete this exception statement from all source
- * files in the program, then also delete it here.
- */
-/* copyright --> */
-#ifndef _D_PEER_OBJECT_H_
-#define _D_PEER_OBJECT_H_
-
-#include "common.h"
-
-namespace aria2 {
-
-class BtMessageFactory;
-class BtRequestFactory;
-class BtMessageDispatcher;
-class BtMessageReceiver;
-class ExtensionMessageFactory;
-class PeerConnection;
-
-class PeerObject {
-public:
-  SharedHandle<BtMessageFactory> btMessageFactory;
-  SharedHandle<BtRequestFactory> btRequestFactory;
-  SharedHandle<BtMessageDispatcher> btMessageDispatcher;
-  SharedHandle<BtMessageReceiver> btMessageReceiver;
-  SharedHandle<PeerConnection> peerConnection;
-  SharedHandle<ExtensionMessageFactory> extensionMessageFactory;
-};
-
-typedef SharedHandle<PeerObject> PeerObjectHandle;
-
-} // namespace aria2
-
-#endif // _D_PEER_OBJECT_H_
diff --git a/src/PeerReceiveHandshakeCommand.cc b/src/PeerReceiveHandshakeCommand.cc
index 0c8b7baa..ad89c13f 100644
--- a/src/PeerReceiveHandshakeCommand.cc
+++ b/src/PeerReceiveHandshakeCommand.cc
@@ -45,6 +45,8 @@
 #include "PeerStorage.h"
 #include "PieceStorage.h"
 #include "BtRuntime.h"
+#include "BtAnnounce.h"
+#include "BtProgressInfoFile.h"
 #include "BtConstants.h"
 #include "message.h"
 #include "Socket.h"
@@ -57,11 +59,13 @@
 
 namespace aria2 {
 
-PeerReceiveHandshakeCommand::PeerReceiveHandshakeCommand(int32_t cuid,
-							 const PeerHandle& peer,
-							 DownloadEngine* e,
-							 const SocketHandle& s,
-							 const SharedHandle<PeerConnection>& peerConnection):
+PeerReceiveHandshakeCommand::PeerReceiveHandshakeCommand
+(int32_t cuid,
+ const PeerHandle& peer,
+ DownloadEngine* e,
+ const SocketHandle& s,
+ const SharedHandle<PeerConnection>& peerConnection)
+  :
   PeerAbstractCommand(cuid, peer, e, s),
   _peerConnection(peerConnection),
   _thresholdSpeed(e->option->getAsInt(PREF_BT_REQUEST_PEER_SPEED_LIMIT))
@@ -93,28 +97,40 @@ bool PeerReceiveHandshakeCommand::executeInternal()
   if(dataLength >= 48) {
     // check info_hash
     std::string infoHash = Util::toHex(&data[28], INFO_HASH_LENGTH);
-    BtContextHandle btContext = BtRegistry::getBtContext(infoHash);
-    if(btContext.isNull() || !BT_RUNTIME(btContext)->ready()) {
+
+    SharedHandle<BtRegistry> btRegistry = e->getBtRegistry();
+    SharedHandle<BtContext> btContext = btRegistry->getBtContext(infoHash);
+    SharedHandle<BtRuntime> btRuntime = btRegistry->getBtRuntime(infoHash);
+    SharedHandle<PieceStorage> pieceStorage =
+      btRegistry->getPieceStorage(infoHash);
+    SharedHandle<PeerStorage> peerStorage =
+      btRegistry->getPeerStorage(infoHash);
+
+    if(btContext.isNull() || !btRuntime->ready()) {
       throw DlAbortEx
 	(StringFormat("Unknown info hash %s", infoHash.c_str()).str());
     }
     TransferStat tstat = btContext->getOwnerRequestGroup()->calculateStat();
-    if((!PIECE_STORAGE(btContext)->downloadFinished() &&
+    if((!pieceStorage->downloadFinished() &&
        tstat.getDownloadSpeed() < _thresholdSpeed) ||
-       BT_RUNTIME(btContext)->lessThanMaxPeers()) {
-      if(PEER_STORAGE(btContext)->addPeer(peer)) {
+       btRuntime->lessThanMaxPeers()) {
+      if(peerStorage->addPeer(peer)) {
 
 	peer->usedBy(cuid);
 	
 	PeerInteractionCommand* command =
-	  new PeerInteractionCommand(cuid,
-				     btContext->getOwnerRequestGroup(),
-				     peer,
-				     e,
-				     btContext,
-				     socket,
-				     PeerInteractionCommand::RECEIVER_WAIT_HANDSHAKE,
-				     _peerConnection);
+	  new PeerInteractionCommand
+	  (cuid,
+	   btContext->getOwnerRequestGroup(),
+	   peer,
+	   e,
+	   btContext,
+	   btRuntime,
+	   pieceStorage,
+	   socket,
+	   PeerInteractionCommand::RECEIVER_WAIT_HANDSHAKE,
+	   _peerConnection);
+	command->setPeerStorage(peerStorage);
 	e->commands.push_back(command);
 	logger->debug(MSG_INCOMING_PEER_CONNECTION, cuid, peer->usedBy());
       }
diff --git a/src/PeerReceiveHandshakeCommand.h b/src/PeerReceiveHandshakeCommand.h
index b0ec6887..d63bcdec 100644
--- a/src/PeerReceiveHandshakeCommand.h
+++ b/src/PeerReceiveHandshakeCommand.h
@@ -54,15 +54,15 @@ protected:
   virtual bool executeInternal();
   virtual bool exitBeforeExecute();
 public:
-  PeerReceiveHandshakeCommand(int32_t cuid,
-			      const SharedHandle<Peer>& peer,
-			      DownloadEngine* e,
-			      const SharedHandle<SocketCore>& s,
-			      const SharedHandle<PeerConnection>& peerConnection = SharedHandle<PeerConnection>());
-
+  PeerReceiveHandshakeCommand
+  (int32_t cuid,
+   const SharedHandle<Peer>& peer,
+   DownloadEngine* e,
+   const SharedHandle<SocketCore>& s,
+   const SharedHandle<PeerConnection>& peerConnection =
+   SharedHandle<PeerConnection>());
+  
   virtual ~PeerReceiveHandshakeCommand();
-
-
 };
 
 } // namespace aria2
diff --git a/src/ReceiverMSEHandshakeCommand.cc b/src/ReceiverMSEHandshakeCommand.cc
index 73f20ef4..9d89e11d 100644
--- a/src/ReceiverMSEHandshakeCommand.cc
+++ b/src/ReceiverMSEHandshakeCommand.cc
@@ -48,6 +48,13 @@
 #include "ARC4Encryptor.h"
 #include "ARC4Decryptor.h"
 #include "RequestGroupMan.h"
+#include "BtRegistry.h"
+#include "BtContext.h"
+#include "PeerStorage.h"
+#include "PieceStorage.h"
+#include "BtAnnounce.h"
+#include "BtRuntime.h"
+#include "BtProgressInfoFile.h"
 
 namespace aria2 {
 
@@ -128,7 +135,8 @@ bool ReceiverMSEHandshakeCommand::executeInternal()
     break;
   }
   case RECEIVER_RECEIVE_PAD_C_LENGTH: {
-    if(_mseHandshake->receiveReceiverHashAndPadCLength()) {
+    if(_mseHandshake->receiveReceiverHashAndPadCLength
+       (e->getBtRegistry()->getAllBtContext())) {
       _sequence = RECEIVER_RECEIVE_PAD_C;
     }
     break;
diff --git a/src/RequestGroup.cc b/src/RequestGroup.cc
index 8a83288f..a1ad0805 100644
--- a/src/RequestGroup.cc
+++ b/src/RequestGroup.cc
@@ -33,6 +33,10 @@
  */
 /* copyright --> */
 #include "RequestGroup.h"
+
+#include <cassert>
+#include <algorithm>
+
 #include "PostDownloadHandler.h"
 #include "DownloadEngine.h"
 #include "DefaultSegmentManFactory.h"
@@ -87,7 +91,6 @@
 # include "BtPostDownloadHandler.h"
 # include "DHTSetup.h"
 # include "DHTRegistry.h"
-# include "PeerObject.h"
 # include "BtMessageFactory.h"
 # include "BtRequestFactory.h"
 # include "BtMessageDispatcher.h"
@@ -100,8 +103,6 @@
 #ifdef ENABLE_METALINK
 # include "MetalinkPostDownloadHandler.h"
 #endif // ENABLE_METALINK
-#include <cassert>
-#include <algorithm>
 
 namespace aria2 {
 
@@ -200,35 +201,46 @@ void RequestGroup::createInitialCommand(std::deque<Command*>& commands,
 	_pieceStorage->setFileFilter(Util::parseIntRange(_option->get(PREF_SELECT_FILE)));
       }
       
-      BtProgressInfoFileHandle
+      SharedHandle<DefaultBtProgressInfoFile>
 	progressInfoFile(new DefaultBtProgressInfoFile(_downloadContext,
 						       _pieceStorage,
 						       _option));
       
-      BtRegistry::registerBtContext(btContext->getInfoHashAsString(), btContext);
-      BtRegistry::registerPieceStorage(btContext->getInfoHashAsString(),
+      SharedHandle<BtRegistry> btRegistry = e->getBtRegistry();
+
+      btRegistry->registerBtContext(btContext->getInfoHashAsString(),
+				    btContext);
+      btRegistry->registerPieceStorage(btContext->getInfoHashAsString(),
 				       _pieceStorage);
-      BtRegistry::registerBtProgressInfoFile(btContext->getInfoHashAsString(),
+      btRegistry->registerBtProgressInfoFile(btContext->getInfoHashAsString(),
 					     progressInfoFile);
 
   
       BtRuntimeHandle btRuntime(new BtRuntime());
       btRuntime->setListenPort(_option->getAsInt(PREF_LISTEN_PORT));
-      BtRegistry::registerBtRuntime(btContext->getInfoHashAsString(), btRuntime);
-
-      PeerStorageHandle peerStorage(new DefaultPeerStorage(btContext, _option));
-      BtRegistry::registerPeerStorage(btContext->getInfoHashAsString(), peerStorage);
-
-      BtAnnounceHandle btAnnounce(new DefaultBtAnnounce(btContext, _option));
-      BtRegistry::registerBtAnnounce(btContext->getInfoHashAsString(), btAnnounce);
+      btRegistry->registerBtRuntime(btContext->getInfoHashAsString(),
+				    btRuntime);
+      _btRuntime = btRuntime;
+      progressInfoFile->setBtRuntime(btRuntime);
+
+      SharedHandle<DefaultPeerStorage> peerStorage
+	(new DefaultPeerStorage(btContext, _option));
+      peerStorage->setBtRuntime(btRuntime);
+      peerStorage->setPieceStorage(_pieceStorage);
+      btRegistry->registerPeerStorage(btContext->getInfoHashAsString(),
+				      peerStorage);
+      _peerStorage = peerStorage;
+      progressInfoFile->setPeerStorage(peerStorage);
+
+      SharedHandle<DefaultBtAnnounce> btAnnounce
+	(new DefaultBtAnnounce(btContext, _option));
+      btAnnounce->setBtRuntime(btRuntime);
+      btAnnounce->setPieceStorage(_pieceStorage);
+      btAnnounce->setPeerStorage(peerStorage);
+      btRegistry->registerBtAnnounce(btContext->getInfoHashAsString(),
+				     btAnnounce);
       btAnnounce->shuffleAnnounce();
       
-      {
-	SharedHandle<PeerObjectCluster> po(new PeerObjectCluster());
-	BtRegistry::registerPeerObjectCluster(btContext->getInfoHashAsString(),
-					      po);
-      }
-
       // Remove the control file if download file doesn't exist
       if(progressInfoFile->exists() && !_pieceStorage->getDiskAdaptor()->fileExists()) {
 	progressInfoFile->removeFile();
@@ -624,14 +636,8 @@ unsigned int RequestGroup::getNumConnection() const
 {
   unsigned int numConnection = _numStreamConnection;
 #ifdef ENABLE_BITTORRENT
-  {
-    BtContextHandle btContext = dynamic_pointer_cast<BtContext>(_downloadContext);
-    if(!btContext.isNull()) {
-      BtRuntimeHandle btRuntime = BT_RUNTIME(btContext);
-      if(!btRuntime.isNull()) {
-	numConnection += btRuntime->getConnections();
-      }
-    }
+  if(!_btRuntime.isNull()) {
+    numConnection += _btRuntime->getConnections();
   }
 #endif // ENABLE_BITTORRENT
   return numConnection;
@@ -652,14 +658,8 @@ TransferStat RequestGroup::calculateStat()
 {
   TransferStat stat;
 #ifdef ENABLE_BITTORRENT
-  {
-    BtContextHandle btContext = dynamic_pointer_cast<BtContext>(_downloadContext);
-    if(!btContext.isNull()) {
-      PeerStorageHandle peerStorage = PEER_STORAGE(btContext);
-      if(!peerStorage.isNull()) {
-	stat = peerStorage->calculateStat();
-      }
-    }
+  if(!_peerStorage.isNull()) {
+    stat = _peerStorage->calculateStat();
   }
 #endif // ENABLE_BITTORRENT
   if(!_segmentMan.isNull()) {
@@ -672,14 +672,8 @@ void RequestGroup::setHaltRequested(bool f)
 {
   _haltRequested = f;
 #ifdef ENABLE_BITTORRENT
-  {
-    BtContextHandle btContext = dynamic_pointer_cast<BtContext>(_downloadContext);
-    if(!btContext.isNull()) {
-      BtRuntimeHandle btRuntime = BT_RUNTIME(btContext);
-      if(!btRuntime.isNull()) {
-	btRuntime->setHalt(f);
-      }
-    }
+  if(!_btRuntime.isNull()) {
+    _btRuntime->setHalt(f);
   }
 #endif // ENABLE_BITTORRENT
 }
@@ -690,18 +684,21 @@ void RequestGroup::setForceHaltRequested(bool f)
   _forceHaltRequested = f;
 }
 
-void RequestGroup::releaseRuntimeResource()
+void RequestGroup::releaseRuntimeResource(DownloadEngine* e)
 {
 #ifdef ENABLE_BITTORRENT
   BtContextHandle btContext = dynamic_pointer_cast<BtContext>(_downloadContext);
   if(!btContext.isNull()) {
-    BtContextHandle btContextInReg = BtRegistry::getBtContext(btContext->getInfoHashAsString());
+    SharedHandle<BtRegistry> btRegistry = e->getBtRegistry();
+    BtContextHandle btContextInReg =
+      btRegistry->getBtContext(btContext->getInfoHashAsString());
     if(!btContextInReg.isNull() &&
        btContextInReg->getOwnerRequestGroup()->getGID() ==
 	btContext->getOwnerRequestGroup()->getGID()) {
-      BtRegistry::unregister(btContext->getInfoHashAsString());
+      btRegistry->unregister(btContext->getInfoHashAsString());
       if(!DHTRegistry::_peerAnnounceStorage.isNull()) {
-	DHTRegistry::_peerAnnounceStorage->removePeerAnnounce(btContext);
+	DHTRegistry::_peerAnnounceStorage->
+	  removeLocalPeerAnnounce(btContext->getInfoHash());
       }
     }
   }
diff --git a/src/RequestGroup.h b/src/RequestGroup.h
index 12dc0fb5..83b175f2 100644
--- a/src/RequestGroup.h
+++ b/src/RequestGroup.h
@@ -36,11 +36,13 @@
 #define _D_REQUEST_GROUP_H_
 
 #include "common.h"
+
+#include <string>
+#include <deque>
+
 #include "SharedHandle.h"
 #include "TransferStat.h"
 #include "TimeA2.h"
-#include <string>
-#include <deque>
 
 namespace aria2 {
 
@@ -62,6 +64,10 @@ class CheckIntegrityEntry;
 class DownloadResult;
 class ServerHost;
 class URISelector;
+#ifdef ENABLE_BITTORRENT
+class BtRuntime;
+class PeerStorage;
+#endif // ENABLE_BITTORRENT
 
 class RequestGroup {
 private:
@@ -120,6 +126,10 @@ private:
 
   unsigned int _fileNotFoundCount;
 
+  WeakHandle<BtRuntime> _btRuntime;
+
+  WeakHandle<PeerStorage> _peerStorage;
+
   const Option* _option;
 
   Logger* _logger;
@@ -287,7 +297,7 @@ public:
 
   bool isDependencyResolved();
 
-  void releaseRuntimeResource();
+  void releaseRuntimeResource(DownloadEngine* e);
 
   void postDownloadProcessing(std::deque<SharedHandle<RequestGroup> >& groups);
 
diff --git a/src/RequestGroupMan.cc b/src/RequestGroupMan.cc
index 8081a37a..4af5cff5 100644
--- a/src/RequestGroupMan.cc
+++ b/src/RequestGroupMan.cc
@@ -122,6 +122,7 @@ RequestGroupMan::getRequestGroups() const
 
 class ProcessStoppedRequestGroup {
 private:
+  DownloadEngine* _e;
   std::deque<SharedHandle<RequestGroup> >& _reservedGroups;
   std::deque<SharedHandle<DownloadResult> >& _downloadResults;
   Logger* _logger;
@@ -143,8 +144,10 @@ private:
   }
 public:
   ProcessStoppedRequestGroup
-  (std::deque<SharedHandle<RequestGroup> >& reservedGroups,
+  (DownloadEngine* e,
+   std::deque<SharedHandle<RequestGroup> >& reservedGroups,
    std::deque<SharedHandle<DownloadResult> >& downloadResults):
+    _e(e),
     _reservedGroups(reservedGroups),
     _downloadResults(downloadResults),
     _logger(LogFactory::getInstance()) {}
@@ -178,7 +181,7 @@ public:
       } catch(RecoverableException& ex) {
 	_logger->error(EX_EXCEPTION_CAUGHT, ex);
       }
-      group->releaseRuntimeResource();
+      group->releaseRuntimeResource(_e);
       _downloadResults.push_back(group->createDownloadResult());
     }
   }
@@ -227,14 +230,15 @@ void RequestGroupMan::updateServerStat()
 		CollectServerStat(this));
 }
 
-void RequestGroupMan::removeStoppedGroup()
+void RequestGroupMan::removeStoppedGroup(DownloadEngine* e)
 {
   size_t numPrev = _requestGroups.size();
 
   updateServerStat();
 
   std::for_each(_requestGroups.begin(), _requestGroups.end(),
-		ProcessStoppedRequestGroup(_reservedGroups, _downloadResults));
+		ProcessStoppedRequestGroup(e, _reservedGroups,
+					   _downloadResults));
 
   _requestGroups.erase(std::remove_if(_requestGroups.begin(),
 				      _requestGroups.end(),
@@ -264,7 +268,7 @@ void RequestGroupMan::configureRequestGroup
 void RequestGroupMan::fillRequestGroupFromReserver(DownloadEngine* e)
 {
   RequestGroups temp;
-  removeStoppedGroup();
+  removeStoppedGroup(e);
   unsigned int count = 0;
   for(int num = _maxSimultaneousDownloads-_requestGroups.size();
       num > 0 && _reservedGroups.size() > 0; --num) {
diff --git a/src/RequestGroupMan.h b/src/RequestGroupMan.h
index 37cb7aaf..f793c4ec 100644
--- a/src/RequestGroupMan.h
+++ b/src/RequestGroupMan.h
@@ -89,7 +89,7 @@ public:
 
   void getInitialCommands(std::deque<Command*>& commands, DownloadEngine* e);
 
-  void removeStoppedGroup();
+  void removeStoppedGroup(DownloadEngine* e);
 
   void fillRequestGroupFromReserver(DownloadEngine* e);
 
diff --git a/src/SeedCheckCommand.cc b/src/SeedCheckCommand.cc
index 7b1bbe6e..48582dcd 100644
--- a/src/SeedCheckCommand.cc
+++ b/src/SeedCheckCommand.cc
@@ -46,17 +46,17 @@ namespace aria2 {
 SeedCheckCommand::SeedCheckCommand(int cuid,
 				   RequestGroup* requestGroup,
 				   DownloadEngine* e,
-				   const BtContextHandle& btContext,
+				   const SharedHandle<BtContext>& btContext,
 				   const SeedCriteriaHandle& seedCriteria)
   :Command(cuid),
-   BtContextAwareCommand(btContext),
    RequestGroupAware(requestGroup),
    e(e),
+   _btContext(btContext),
    seedCriteria(seedCriteria),
    checkStarted(false) {}
 
 bool SeedCheckCommand::execute() {
-  if(btRuntime->isHalt()) {
+  if(_btRuntime->isHalt()) {
     return true;
   }
   if(!seedCriteria.get()) {
@@ -64,7 +64,7 @@ bool SeedCheckCommand::execute() {
   }
   if(checkPoint.elapsed(1)) {
     if(!checkStarted) {
-      if(pieceStorage->downloadFinished()) {
+      if(_pieceStorage->downloadFinished()) {
 	checkStarted = true;
 	seedCriteria->reset();
       }
@@ -72,7 +72,7 @@ bool SeedCheckCommand::execute() {
     if(checkStarted) {
       if(seedCriteria->evaluate()) {
 	logger->notice(MSG_SEEDING_END);
-	btRuntime->setHalt(true);
+	_btRuntime->setHalt(true);
       }
     }
   }
@@ -80,9 +80,22 @@ bool SeedCheckCommand::execute() {
   return false;
 }
 
-void SeedCheckCommand::setSeedCriteria(const SharedHandle<SeedCriteria>& seedCriteria)
+void SeedCheckCommand::setSeedCriteria
+(const SharedHandle<SeedCriteria>& seedCriteria)
 {
   this->seedCriteria = seedCriteria;
 }
 
+void SeedCheckCommand::setBtRuntime(const SharedHandle<BtRuntime>& btRuntime)
+{
+  _btRuntime = btRuntime;
+}
+
+void SeedCheckCommand::setPieceStorage
+(const SharedHandle<PieceStorage>& pieceStorage)
+{
+  _pieceStorage = pieceStorage;
+}
+
+
 } // namespace aria2
diff --git a/src/SeedCheckCommand.h b/src/SeedCheckCommand.h
index 843c31c2..c82061a1 100644
--- a/src/SeedCheckCommand.h
+++ b/src/SeedCheckCommand.h
@@ -36,7 +36,7 @@
 #define _D_SEED_CHECK_COMMAND_H_
 
 #include "Command.h"
-#include "BtContextAwareCommand.h"
+#include "SharedHandle.h"
 #include "RequestGroupAware.h"
 #include "TimeA2.h"
 
@@ -44,13 +44,18 @@ namespace aria2 {
 
 class DownloadEngine;
 class SeedCriteria;
+class BtContext;
+class BtRuntime;
+class PieceStorage;
 
 class SeedCheckCommand : public Command,
-			 public BtContextAwareCommand,
 			 public RequestGroupAware
 {
 private:
   DownloadEngine* e;
+  SharedHandle<BtContext> _btContext;
+  SharedHandle<PieceStorage> _pieceStorage;
+  SharedHandle<BtRuntime> _btRuntime;
   Time checkPoint;
   SharedHandle<SeedCriteria> seedCriteria;
   bool checkStarted;
@@ -66,6 +71,10 @@ public:
   virtual bool execute();
 
   void setSeedCriteria(const SharedHandle<SeedCriteria>& seedCriteria);
+
+  void setBtRuntime(const SharedHandle<BtRuntime>& btRuntime);
+
+  void setPieceStorage(const SharedHandle<PieceStorage>& pieceStorage);
 };
 
 } // namespace aria2
diff --git a/src/ShareRatioSeedCriteria.h b/src/ShareRatioSeedCriteria.h
index 8a6b4115..41a8ae92 100644
--- a/src/ShareRatioSeedCriteria.h
+++ b/src/ShareRatioSeedCriteria.h
@@ -40,7 +40,6 @@
 #include "PeerStorage.h"
 #include "PieceStorage.h"
 #include "BtRuntime.h"
-#include "BtRegistry.h"
 
 namespace aria2 {
 
@@ -48,16 +47,13 @@ class ShareRatioSeedCriteria : public SeedCriteria {
 private:
   double ratio;
   SharedHandle<BtContext> btContext;
-  SharedHandle<PeerStorage> peerStorage;
-  SharedHandle<PieceStorage> pieceStorage;
-  SharedHandle<BtRuntime> btRuntime;
+  SharedHandle<PeerStorage> _peerStorage;
+  SharedHandle<PieceStorage> _pieceStorage;
+  SharedHandle<BtRuntime> _btRuntime;
 public:
   ShareRatioSeedCriteria(double ratio, const SharedHandle<BtContext>& btContext)
     :ratio(ratio),
-     btContext(btContext),
-     peerStorage(PEER_STORAGE(btContext)),
-     pieceStorage(PIECE_STORAGE(btContext)),
-     btRuntime(BT_RUNTIME(btContext)) {}
+     btContext(btContext) {}
 
   virtual ~ShareRatioSeedCriteria() {}
 
@@ -67,11 +63,11 @@ public:
     if(btContext->getTotalLength() == 0) {
       return false;
     }
-    TransferStat stat = peerStorage->calculateStat();
+    TransferStat stat = _peerStorage->calculateStat();
     uint64_t allTimeUploadLength =
-      btRuntime->getUploadLengthAtStartup()+stat.getSessionUploadLength();
+      _btRuntime->getUploadLengthAtStartup()+stat.getSessionUploadLength();
     return ratio <=
-      ((double)allTimeUploadLength)/pieceStorage->getCompletedLength();
+      ((double)allTimeUploadLength)/_pieceStorage->getCompletedLength();
   }
 
   void setRatio(double ratio) {
@@ -81,6 +77,21 @@ public:
   double getRatio() const {
     return ratio;
   }
+
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage)
+  {
+    _peerStorage = peerStorage;
+  }
+
+  void setPieceStorage(const SharedHandle<PieceStorage>& pieceStorage)
+  {
+    _pieceStorage = pieceStorage;
+  }
+
+  void setBtRuntime(const SharedHandle<BtRuntime>& btRuntime)
+  {
+    _btRuntime = btRuntime;
+  }
 };
 
 } // namespace aria2
diff --git a/src/SimpleBtMessage.cc b/src/SimpleBtMessage.cc
index 99c8d0f7..c22c34a5 100644
--- a/src/SimpleBtMessage.cc
+++ b/src/SimpleBtMessage.cc
@@ -34,7 +34,6 @@
 /* copyright --> */
 #include "SimpleBtMessage.h"
 #include "message.h"
-#include "BtRegistry.h"
 #include "Peer.h"
 #include "PeerConnection.h"
 #include "Logger.h"
diff --git a/src/TrackerWatcherCommand.cc b/src/TrackerWatcherCommand.cc
index 2271d828..98869f1b 100644
--- a/src/TrackerWatcherCommand.cc
+++ b/src/TrackerWatcherCommand.cc
@@ -33,6 +33,9 @@
  */
 /* copyright --> */
 #include "TrackerWatcherCommand.h"
+
+#include <sstream>
+
 #include "DownloadEngine.h"
 #include "BtContext.h"
 #include "BtAnnounce.h"
@@ -55,7 +58,6 @@
 #include "Logger.h"
 #include "A2STR.h"
 #include "SocketCore.h"
-#include <sstream>
 
 namespace aria2 {
 
@@ -64,9 +66,9 @@ TrackerWatcherCommand::TrackerWatcherCommand(int32_t cuid,
 					     DownloadEngine* e,
 					     const BtContextHandle& btContext):
   Command(cuid),
-  BtContextAwareCommand(btContext),
   RequestGroupAware(requestGroup),
-  e(e) {}
+  e(e),
+  _btContext(btContext) {}
 
 TrackerWatcherCommand::~TrackerWatcherCommand() {}
 
@@ -83,7 +85,7 @@ bool TrackerWatcherCommand::execute() {
       return false;
     }
   }
-  if(btAnnounce->noMoreAnnounce()) {
+  if(_btAnnounce->noMoreAnnounce()) {
     logger->debug("no more announce");
     return true;
   }
@@ -100,35 +102,37 @@ bool TrackerWatcherCommand::execute() {
       std::string trackerResponse = getTrackerResponse(_trackerRequestGroup);
 
       processTrackerResponse(trackerResponse);
-      btAnnounce->announceSuccess();
-      btAnnounce->resetAnnounce();
+      _btAnnounce->announceSuccess();
+      _btAnnounce->resetAnnounce();
     } catch(RecoverableException& ex) {
       logger->error(EX_EXCEPTION_CAUGHT, ex);      
-      btAnnounce->announceFailure();
-      if(btAnnounce->isAllAnnounceFailed()) {
-	btAnnounce->resetAnnounce();
+      _btAnnounce->announceFailure();
+      if(_btAnnounce->isAllAnnounceFailed()) {
+	_btAnnounce->resetAnnounce();
       }
     }
     _trackerRequestGroup.reset();
   } else if(_trackerRequestGroup->getNumCommand() == 0){
     // handle errors here
-    btAnnounce->announceFailure(); // inside it, trackers = 0.
+    _btAnnounce->announceFailure(); // inside it, trackers = 0.
     _trackerRequestGroup.reset();
-    if(btAnnounce->isAllAnnounceFailed()) {
-      btAnnounce->resetAnnounce();
+    if(_btAnnounce->isAllAnnounceFailed()) {
+      _btAnnounce->resetAnnounce();
     }
   }
   e->commands.push_back(this);
   return false;
 }
 
-std::string TrackerWatcherCommand::getTrackerResponse(const RequestGroupHandle& requestGroup)
+std::string TrackerWatcherCommand::getTrackerResponse
+(const RequestGroupHandle& requestGroup)
 {
   std::stringstream strm;
   unsigned char data[2048];
   requestGroup->getPieceStorage()->getDiskAdaptor()->openFile();
   while(1) {
-    ssize_t dataLength = requestGroup->getPieceStorage()->getDiskAdaptor()->readData(data, sizeof(data), strm.tellp());
+    ssize_t dataLength = requestGroup->getPieceStorage()->
+      getDiskAdaptor()->readData(data, sizeof(data), strm.tellp());
     if(dataLength == 0) {
       break;
     }
@@ -138,12 +142,14 @@ std::string TrackerWatcherCommand::getTrackerResponse(const RequestGroupHandle&
 }
 
 // TODO we have to deal with the exception thrown By BtAnnounce
-void TrackerWatcherCommand::processTrackerResponse(const std::string& trackerResponse)
+void TrackerWatcherCommand::processTrackerResponse
+(const std::string& trackerResponse)
 {
-  btAnnounce->processAnnounceResponse(reinterpret_cast<const unsigned char*>(trackerResponse.c_str()),
+  _btAnnounce->processAnnounceResponse
+    (reinterpret_cast<const unsigned char*>(trackerResponse.c_str()),
 				      trackerResponse.size());
-  while(!btRuntime->isHalt() && btRuntime->lessThanMinPeers()) {
-    PeerHandle peer = peerStorage->getUnusedPeer();
+  while(!_btRuntime->isHalt() && _btRuntime->lessThanMinPeers()) {
+    PeerHandle peer = _peerStorage->getUnusedPeer();
     if(peer.isNull()) {
       break;
     }
@@ -153,7 +159,10 @@ void TrackerWatcherCommand::processTrackerResponse(const std::string& trackerRes
 					_requestGroup,
 					peer,
 					e,
-					btContext);
+					_btContext,
+					_btRuntime);
+    command->setPeerStorage(_peerStorage);
+    command->setPieceStorage(_pieceStorage);
     e->commands.push_back(command);
     logger->debug("CUID#%d - Adding new command CUID#%d", cuid, peer->usedBy());
   }
@@ -161,9 +170,9 @@ void TrackerWatcherCommand::processTrackerResponse(const std::string& trackerRes
 
 RequestGroupHandle TrackerWatcherCommand::createAnnounce() {
   RequestGroupHandle rg;
-  if(btAnnounce->isAnnounceReady()) {
-    rg = createRequestGroup(btAnnounce->getAnnounceUrl());
-    btAnnounce->announceStart(); // inside it, trackers++.
+  if(_btAnnounce->isAnnounceReady()) {
+    rg = createRequestGroup(_btAnnounce->getAnnounceUrl());
+    _btAnnounce->announceStart(); // inside it, trackers++.
   }
   return rg;
 }
@@ -191,4 +200,28 @@ TrackerWatcherCommand::createRequestGroup(const std::string& uri)
   return rg;
 }
 
+void TrackerWatcherCommand::setBtRuntime
+(const SharedHandle<BtRuntime>& btRuntime)
+{
+  _btRuntime = btRuntime;
+}
+
+void TrackerWatcherCommand::setPeerStorage
+(const SharedHandle<PeerStorage>& peerStorage)
+{
+  _peerStorage = peerStorage;
+}
+
+void TrackerWatcherCommand::setPieceStorage
+(const SharedHandle<PieceStorage>& pieceStorage)
+{
+  _pieceStorage = pieceStorage;
+}
+
+void TrackerWatcherCommand::setBtAnnounce
+(const SharedHandle<BtAnnounce>& btAnnounce)
+{
+  _btAnnounce = btAnnounce;
+}
+
 } // namespace aria2
diff --git a/src/TrackerWatcherCommand.h b/src/TrackerWatcherCommand.h
index f5c59de8..3611dc7e 100644
--- a/src/TrackerWatcherCommand.h
+++ b/src/TrackerWatcherCommand.h
@@ -36,21 +36,35 @@
 #define _D_TRACKER_WATCHER_COMMAND_H_
 
 #include "Command.h"
-#include "BtContextAwareCommand.h"
+#include "SharedHandle.h"
 #include "RequestGroupAware.h"
 
 namespace aria2 {
 
 class DownloadEngine;
 class RequestGroup;
+class BtContext;
+class PeerStorage;
+class PieceStorage;
+class BtRuntime;
+class BtAnnounce;
 
 class TrackerWatcherCommand : public Command,
-			      public BtContextAwareCommand,
 			      public RequestGroupAware
 {
 private:
   DownloadEngine* e;
 
+  SharedHandle<BtContext> _btContext;
+
+  SharedHandle<PeerStorage> _peerStorage;
+
+  SharedHandle<PieceStorage> _pieceStorage;
+
+  SharedHandle<BtRuntime> _btRuntime;
+
+  SharedHandle<BtAnnounce> _btAnnounce;
+
   SharedHandle<RequestGroup> _trackerRequestGroup;
   /**
    * Returns a command for announce request. Returns 0 if no announce request
@@ -73,6 +87,14 @@ public:
   SharedHandle<RequestGroup> createAnnounce();
 
   virtual bool execute();
+
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
+
+  void setPieceStorage(const SharedHandle<PieceStorage>& pieceStorage);
+
+  void setBtRuntime(const SharedHandle<BtRuntime>& btRuntime);
+
+  void setBtAnnounce(const SharedHandle<BtAnnounce>& btAnnounce);
 };
 
 } // namespace aria2
diff --git a/src/UTPexExtensionMessage.cc b/src/UTPexExtensionMessage.cc
index fb7bfd7b..892483b1 100644
--- a/src/UTPexExtensionMessage.cc
+++ b/src/UTPexExtensionMessage.cc
@@ -34,13 +34,11 @@
 /* copyright --> */
 #include "UTPexExtensionMessage.h"
 #include "Peer.h"
-#include "BtContext.h"
 #include "Dictionary.h"
 #include "Data.h"
 #include "BencodeVisitor.h"
 #include "Util.h"
 #include "PeerMessageUtil.h"
-#include "BtRegistry.h"
 #include "PeerStorage.h"
 #include "CompactPeerListProcessor.h"
 #include "MetaFileUtil.h"
@@ -96,7 +94,7 @@ std::string UTPexExtensionMessage::toString() const
 
 void UTPexExtensionMessage::doReceivedAction()
 {
-  PEER_STORAGE(_btContext)->addPeer(_freshPeers);
+  _peerStorage->addPeer(_freshPeers);
 }
 
 bool UTPexExtensionMessage::addFreshPeer(const PeerHandle& peer)
@@ -161,14 +159,14 @@ size_t UTPexExtensionMessage::getMaxDroppedPeer() const
   return _maxDroppedPeer;
 }
 
-void UTPexExtensionMessage::setBtContext(const BtContextHandle& btContext)
+void UTPexExtensionMessage::setPeerStorage
+(const SharedHandle<PeerStorage>& peerStorage)
 {
-  _btContext = btContext;
+  _peerStorage = peerStorage;
 }
 
 UTPexExtensionMessageHandle
-UTPexExtensionMessage::create(const BtContextHandle& btContext,
-			      const unsigned char* data, size_t len)
+UTPexExtensionMessage::create(const unsigned char* data, size_t len)
 {
   if(len < 1) {
     throw DlAbortEx(StringFormat(MSG_TOO_SMALL_PAYLOAD_SIZE,
diff --git a/src/UTPexExtensionMessage.h b/src/UTPexExtensionMessage.h
index 41b38119..7bf19073 100644
--- a/src/UTPexExtensionMessage.h
+++ b/src/UTPexExtensionMessage.h
@@ -36,13 +36,15 @@
 #define _D_UT_PEX_EXTENSION_MESSAGE_H_
 
 #include "ExtensionMessage.h"
-#include "a2time.h"
+
 #include <utility>
 #include <deque>
 
+#include "a2time.h"
+
 namespace aria2 {
 
-class BtContext;
+class PeerStorage;
 class Peer;
 class UTPexExtensionMessage;
 typedef SharedHandle<UTPexExtensionMessage> UTPexExtensionMessageHandle;
@@ -55,7 +57,7 @@ private:
 
   std::deque<SharedHandle<Peer> > _droppedPeers;
 
-  SharedHandle<BtContext> _btContext;
+  SharedHandle<PeerStorage> _peerStorage;
 
   time_t _interval;
 
@@ -101,10 +103,10 @@ public:
 
   bool droppedPeersAreFull() const;
 
-  void setBtContext(const SharedHandle<BtContext>& btContext);
+  void setPeerStorage(const SharedHandle<PeerStorage>& peerStorage);
 
-  static UTPexExtensionMessageHandle create(const SharedHandle<BtContext>& btContext,
-					    const unsigned char* data, size_t len);
+  static UTPexExtensionMessageHandle
+  create(const unsigned char* data, size_t len);
 
   void setMaxFreshPeer(size_t maxFreshPeer);