Added the ability to plug in your own subscription manager. This way you

can implement caching if you want to, or not if you don't want to.
Existing applications should be unaffected.

src/main/java/net/engio/mbassy/bus/AbstractSyncMessageBus.java

@@ -35,7 +35,8 @@ public abstract class AbstractSyncMessageBus<T, P extends IPublicationCommand> i
     public AbstractSyncMessageBus(ISyncBusConfiguration configuration) {
         this.runtime = new BusRuntime(this);
         this.runtime.add("error.handlers", getRegisteredErrorHandlers());
-        this.subscriptionManager = new SubscriptionManager(configuration.getMetadataReader(),
+        this.subscriptionManager = configuration.getSubscriptionManagerProvider()
+        		.createManager(configuration.getMetadataReader(),
                 configuration.getSubscriptionFactory(), runtime);
         this.publicationFactory = configuration.getMessagePublicationFactory();
     }

src/main/java/net/engio/mbassy/bus/config/BusConfiguration.java

@@ -2,7 +2,9 @@ package net.engio.mbassy.bus.config;
 
 import net.engio.mbassy.bus.MessagePublication;
 import net.engio.mbassy.listener.MetadataReader;
+import net.engio.mbassy.subscription.ISubscriptionManagerProvider;
 import net.engio.mbassy.subscription.SubscriptionFactory;
+import net.engio.mbassy.subscription.SubscriptionManagerProvider;
 
 import java.util.concurrent.*;
 import java.util.concurrent.atomic.AtomicInteger;
@@ -95,6 +97,7 @@ public class BusConfiguration implements IBusConfiguration {
         defaultConfig.setMessagePublicationFactory(new MessagePublication.Factory());
         defaultConfig.setPendingMessagesQueue(new LinkedBlockingQueue<MessagePublication>(Integer.MAX_VALUE));
         defaultConfig.setThreadFactoryForAsynchronousMessageDispatch(DispatcherThreadFactory);
+        defaultConfig.setSubscriptionManagerProvider(new SubscriptionManagerProvider());
         return defaultConfig;
     }
 
@@ -108,6 +111,7 @@ public class BusConfiguration implements IBusConfiguration {
     protected MetadataReader metadataReader;
     protected MessagePublication.Factory messagePublicationFactory;
     protected ThreadFactory dispatcherThreadFactory;
+    protected ISubscriptionManagerProvider subscriptionManagerProvider;
 
     public void setPendingMessagesQueue(BlockingQueue<MessagePublication> pendingMessagesQueue) {
         this.pendingMessagesQueue = pendingMessagesQueue;
@@ -184,4 +188,11 @@ public class BusConfiguration implements IBusConfiguration {
         return this;
     }
 
+    public ISubscriptionManagerProvider getSubscriptionManagerProvider() {
+    	return subscriptionManagerProvider;
+    }
+    
+    public void setSubscriptionManagerProvider(ISubscriptionManagerProvider subscriptionManagerProvider) {
+    	this.subscriptionManagerProvider = subscriptionManagerProvider;
+    }
 }

src/main/java/net/engio/mbassy/bus/config/ISyncBusConfiguration.java

@@ -2,6 +2,7 @@ package net.engio.mbassy.bus.config;
 
 import net.engio.mbassy.bus.MessagePublication;
 import net.engio.mbassy.listener.MetadataReader;
+import net.engio.mbassy.subscription.ISubscriptionManagerProvider;
 import net.engio.mbassy.subscription.SubscriptionFactory;
 
 public interface ISyncBusConfiguration {
@@ -11,5 +12,7 @@ public interface ISyncBusConfiguration {
 	MetadataReader getMetadataReader();
 
 	SubscriptionFactory getSubscriptionFactory();
+	
+	ISubscriptionManagerProvider getSubscriptionManagerProvider();
 
 }

src/main/java/net/engio/mbassy/bus/config/SyncBusConfiguration.java

@@ -2,7 +2,9 @@ package net.engio.mbassy.bus.config;
 
 import net.engio.mbassy.bus.MessagePublication;
 import net.engio.mbassy.listener.MetadataReader;
+import net.engio.mbassy.subscription.ISubscriptionManagerProvider;
 import net.engio.mbassy.subscription.SubscriptionFactory;
+import net.engio.mbassy.subscription.SubscriptionManagerProvider;
 
 /**
  * Todo: Add javadoc
@@ -15,11 +17,13 @@ public class SyncBusConfiguration<C extends SyncBusConfiguration<C>> implements
     protected SubscriptionFactory subscriptionFactory;
     protected MetadataReader metadataReader;
     protected MessagePublication.Factory messagePublicationFactory;
+    protected ISubscriptionManagerProvider subscriptionManagerProvider;
 
     public SyncBusConfiguration() {
         this.metadataReader = new MetadataReader();
         this.subscriptionFactory = new SubscriptionFactory();
         this.messagePublicationFactory = new MessagePublication.Factory();
+        this.subscriptionManagerProvider = new SubscriptionManagerProvider();
     }
 
     public MessagePublication.Factory getMessagePublicationFactory() {
@@ -47,4 +51,13 @@ public class SyncBusConfiguration<C extends SyncBusConfiguration<C>> implements
         this.subscriptionFactory = subscriptionFactory;
         return (C) this;
     }
+    
+    public ISubscriptionManagerProvider getSubscriptionManagerProvider() {
+    	return subscriptionManagerProvider;
+    }
+    
+    public C setSubscriptionManagerProvider(ISubscriptionManagerProvider subscriptionManagerProvider) {
+    	this.subscriptionManagerProvider = subscriptionManagerProvider;
+    	return (C) this;
+    }
 }

src/main/java/net/engio/mbassy/subscription/ISubscriptionManagerProvider.java

@@ -0,0 +1,9 @@
+package net.engio.mbassy.subscription;
+
+import net.engio.mbassy.bus.BusRuntime;
+import net.engio.mbassy.listener.MetadataReader;
+
+public interface ISubscriptionManagerProvider {
+	SubscriptionManager createManager(MetadataReader reader,
+			SubscriptionFactory factory, BusRuntime runtime);
+}

src/main/java/net/engio/mbassy/subscription/SubscriptionManagerProvider.java

@@ -0,0 +1,12 @@
+package net.engio.mbassy.subscription;
+
+import net.engio.mbassy.bus.BusRuntime;
+import net.engio.mbassy.listener.MetadataReader;
+
+public class SubscriptionManagerProvider implements ISubscriptionManagerProvider {
+	@Override
+	public SubscriptionManager createManager(MetadataReader reader,
+			SubscriptionFactory factory, BusRuntime runtime) {
+		return new SubscriptionManager(reader, factory, runtime);
+	}
+}