Add the ability to see registered asynchronous listeners.

ProtocolLib/src/main/java/com/comphenix/protocol/AsynchronousManager.java

@@ -136,8 +136,14 @@ public interface AsynchronousManager {
 	public abstract void unregisterTimeoutHandler(PacketListener listener);
 
 	/**
-	 * Get a immutable list of every registered timeout handler.
+	 * Get a immutable set of every registered timeout handler.
-	 * @return List of every registered timeout handler.
+	 * @return Set of every registered timeout handler.
 	 */
 	public abstract Set<PacketListener> getTimeoutHandlers();
+
+	/**
+	 * Get an immutable set of every registered asynchronous packet listener.
+	 * @return Set of every asynchronous packet listener.
+	 */
+	public abstract Set<PacketListener> getAsyncHandlers();
 }

ProtocolLib/src/main/java/com/comphenix/protocol/CommandProtocol.java

@@ -82,10 +82,17 @@ class CommandProtocol extends CommandBase {
 	
 	// Display every listener on the server
 	private void printListeners(final CommandSender sender, String[] args) {
-		for (PacketListener listener : ProtocolLibrary.getProtocolManager().getPacketListeners()) {
+		ProtocolManager manager = ProtocolLibrary.getProtocolManager();
+		
+		for (PacketListener listener : manager.getPacketListeners()) {
 			sender.sendMessage(ChatColor.GOLD + "Packet listeners:");
 			sender.sendMessage(ChatColor.GOLD + " " + listener);
 		}
+		// Along with every asynchronous listener
+		for (PacketListener listener : manager.getAsynchronousManager().getAsyncHandlers()) {
+			sender.sendMessage(ChatColor.GOLD + "Asynchronous listeners:");
+			sender.sendMessage(ChatColor.GOLD + " " + listener);
+		}
 	}
 	
 	private void performUpdate(final CommandSender sender, UpdateType type) {

ProtocolLib/src/main/java/com/comphenix/protocol/PacketTypeLookup.java

@@ -7,8 +7,6 @@ import com.comphenix.protocol.PacketType.Protocol;
 import com.comphenix.protocol.PacketType.Sender;
 import com.comphenix.protocol.collections.IntegerMap;
 import com.google.common.base.Preconditions;
-import com.google.common.collect.BiMap;
-import com.google.common.collect.HashBiMap;
 import com.google.common.collect.HashMultimap;
 import com.google.common.collect.Multimap;
 

ProtocolLib/src/main/java/com/comphenix/protocol/async/AsyncFilterManager.java

@@ -41,6 +41,7 @@ import com.comphenix.protocol.injector.SortedPacketListenerList;
 import com.comphenix.protocol.injector.packet.PacketRegistry;
 import com.google.common.base.Objects;
 import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Iterables;
 import com.google.common.collect.Sets;
 
 /**
@@ -142,6 +143,18 @@ public class AsyncFilterManager implements AsynchronousManager {
 		return ImmutableSet.copyOf(timeoutListeners);
 	}
 	
+	@Override
+	public Set<PacketListener> getAsyncHandlers() {
+		ImmutableSet.Builder<PacketListener> builder = ImmutableSet.builder();
+		
+		// Add every asynchronous packet listener
+		for (PrioritizedListener<AsyncListenerHandler> handler : 
+				Iterables.concat(serverProcessingQueue.values(), clientProcessingQueue.values())) {
+			builder.add(handler.getListener().getAsyncListener());
+		}
+		return builder.build();
+	}
+	
 	/**
 	 * Registers an asynchronous packet handler.
 	 * <p>