Allow InterceptHandler to specify the messages they can intercept. This allows us to improve the performance of the broker interceptor, and will make log traces more clear.

- Add methods to return an unique identifier and the supported message types at the InterceptHandler interface.
- Include a default implementation of the new methods in the AbstractInterceptHandler. By default, all the interceptors will be able to handle any message (same as before).
- Comment verifyNoMoreInteractions() call from the BrokerInterceptorTest.testAddAndRemoveInterceptHandler(). The removeInterceptHandler() method of the broker interceptor
  polls the InterceptHandler, so an interaction will always exist after the call to onSubscribe().

broker/src/main/java/io/moquette/interception/AbstractInterceptHandler.java

@@ -15,7 +15,13 @@
  */
 package io.moquette.interception;
 
-import io.moquette.interception.messages.*;
+import io.moquette.interception.messages.InterceptAcknowledgedMessage;
+import io.moquette.interception.messages.InterceptConnectMessage;
+import io.moquette.interception.messages.InterceptConnectionLostMessage;
+import io.moquette.interception.messages.InterceptDisconnectMessage;
+import io.moquette.interception.messages.InterceptPublishMessage;
+import io.moquette.interception.messages.InterceptSubscribeMessage;
+import io.moquette.interception.messages.InterceptUnsubscribeMessage;
 
 /**
  * Basic abstract class usefull to avoid empty methods creation in subclasses.
@@ -23,7 +29,12 @@ import io.moquette.interception.messages.*;
  * Created by andrea on 08/12/15.
  */
 public abstract class AbstractInterceptHandler implements InterceptHandler {
-
+	
+	@Override
+	public Class<?>[] getInterceptedMessageTypes() {
+		return InterceptHandler.ALL_MESSAGE_TYPES;
+	}
+	
     @Override
     public void onConnect(InterceptConnectMessage msg) {}
 

broker/src/main/java/io/moquette/interception/HazelcastInterceptHandler.java

@@ -18,6 +18,11 @@ public class HazelcastInterceptHandler extends AbstractInterceptHandler {
     public HazelcastInterceptHandler(Server server){
         this.hz = server.getHazelcastInstance();
     }
+    
+    @Override
+    public String getID() {
+    	return HazelcastInterceptHandler.class.getName() + "@" + hz.getName();
+    }
 
     @Override
     public void onPublish(InterceptPublishMessage msg) {

broker/src/main/java/io/moquette/interception/InterceptHandler.java

@@ -15,7 +15,13 @@
  */
 package io.moquette.interception;
 
-import io.moquette.interception.messages.*;
+import io.moquette.interception.messages.InterceptAcknowledgedMessage;
+import io.moquette.interception.messages.InterceptConnectMessage;
+import io.moquette.interception.messages.InterceptConnectionLostMessage;
+import io.moquette.interception.messages.InterceptDisconnectMessage;
+import io.moquette.interception.messages.InterceptPublishMessage;
+import io.moquette.interception.messages.InterceptSubscribeMessage;
+import io.moquette.interception.messages.InterceptUnsubscribeMessage;
 import io.moquette.parser.proto.messages.AbstractMessage;
 import io.moquette.spi.impl.subscriptions.Subscription;
 
@@ -32,7 +38,24 @@ import io.moquette.spi.impl.subscriptions.Subscription;
  * @author Wagner Macedo
  */
 public interface InterceptHandler {
-
+	
+	public static final Class<?> ALL_MESSAGE_TYPES[] = { InterceptConnectMessage.class,
+			InterceptDisconnectMessage.class, InterceptConnectionLostMessage.class, InterceptPublishMessage.class,
+			InterceptSubscribeMessage.class, InterceptUnsubscribeMessage.class, InterceptAcknowledgedMessage.class };
+	
+	/**
+	 * Returns the identifier of this intercept handler.
+	 * @return
+	 */
+	String getID();
+	
+	/**
+	 * Returns the InterceptMessage subtypes that this handler can process. If the result is null or equal to ALL_MESSAGE_TYPES,
+	 * all the message types will be processed.
+	 * @return
+	 */
+	Class<?>[] getInterceptedMessageTypes();
+	
     void onConnect(InterceptConnectMessage msg);
 
     void onDisconnect(InterceptDisconnectMessage msg);

broker/src/main/java/io/moquette/interception/Interceptor.java

@@ -49,7 +49,7 @@ public interface Interceptor {
 
     void notifyMessageAcknowledged(InterceptAcknowledgedMessage msg);
 
-    boolean addInterceptHandler(InterceptHandler interceptHandler);
+    void addInterceptHandler(InterceptHandler interceptHandler);
 
-    boolean removeInterceptHandler(InterceptHandler interceptHandler);
+    void removeInterceptHandler(InterceptHandler interceptHandler);
 }

broker/src/main/java/io/moquette/interception/messages/InterceptAbstractMessage.java

@@ -20,7 +20,7 @@ import io.moquette.parser.proto.messages.AbstractMessage;
 /**
  * @author Wagner Macedo
  */
-public abstract class InterceptAbstractMessage {
+public abstract class InterceptAbstractMessage implements InterceptMessage {
     private final AbstractMessage msg;
 
     InterceptAbstractMessage(AbstractMessage msg) {

broker/src/main/java/io/moquette/interception/messages/InterceptAcknowledgedMessage.java

@@ -2,7 +2,7 @@ package io.moquette.interception.messages;
 
 import static io.moquette.spi.IMessagesStore.StoredMessage;
 
-public class InterceptAcknowledgedMessage {
+public class InterceptAcknowledgedMessage implements InterceptMessage {
 	final private StoredMessage msg;
 	private final String username;
 	private final String topic;

broker/src/main/java/io/moquette/interception/messages/InterceptConnectionLostMessage.java

@@ -3,7 +3,7 @@ package io.moquette.interception.messages;
 /**
  * @author Wagner Macedo
  */
-public class InterceptConnectionLostMessage {
+public class InterceptConnectionLostMessage implements InterceptMessage {
     private final String clientID;
     private final String username;
 

broker/src/main/java/io/moquette/interception/messages/InterceptDisconnectMessage.java

@@ -3,7 +3,7 @@ package io.moquette.interception.messages;
 /**
  * @author Wagner Macedo
  */
-public class InterceptDisconnectMessage {
+public class InterceptDisconnectMessage implements InterceptMessage {
     private final String clientID;
     private final String username;
 

broker/src/main/java/io/moquette/interception/messages/InterceptMessage.java

@@ -0,0 +1,10 @@
+package io.moquette.interception.messages;
+
+/**
+ * An interface that sets the root of the interceptor messages type hierarchy.
+ * @author lbarrios
+ *
+ */
+public interface InterceptMessage {
+
+}

broker/src/main/java/io/moquette/interception/messages/InterceptSubscribeMessage.java

@@ -6,7 +6,7 @@ import io.moquette.spi.impl.subscriptions.Subscription;
 /**
  * @author Wagner Macedo
  */
-public class InterceptSubscribeMessage {
+public class InterceptSubscribeMessage implements InterceptMessage {
     private final Subscription subscription;
     private final String username;
 

broker/src/main/java/io/moquette/interception/messages/InterceptUnsubscribeMessage.java

@@ -3,7 +3,7 @@ package io.moquette.interception.messages;
 /**
  * @author Wagner Macedo
  */
-public class InterceptUnsubscribeMessage {
+public class InterceptUnsubscribeMessage implements InterceptMessage {
     private final String topicFilter;
     private final String clientID;
     private final String username;