Ack packet detection bug fixed

src/main/java/com/corundumstudio/socketio/PacketHandler.java

@@ -15,6 +15,8 @@
  */
 package com.corundumstudio.socketio;
 
+import java.util.Collections;
+
 import org.jboss.netty.buffer.ChannelBuffer;
 import org.jboss.netty.channel.ChannelHandler.Sharable;
 import org.jboss.netty.channel.ChannelHandlerContext;
@@ -64,7 +66,7 @@ public class PacketHandler extends SimpleChannelUpstreamHandler {
                 SocketIOClient client = message.getClient().getChildClient(ns);
                 AckRequest ackSender = new AckRequest(packet, client);
                 packetListener.onPacket(packet, client, ackSender);
-                ackSender.sendAckData((Object)null);
+                ackSender.sendAckData(Collections.emptyList());
             }
         } else {
             ctx.sendUpstream(e);

src/main/java/com/corundumstudio/socketio/parser/Packet.java

@@ -138,8 +138,16 @@ public class Packet {
         this.advice = advice;
     }
 
+    private boolean isJsonAck() {
+        return (Boolean.TRUE.equals(getAck()) || ACK_DATA.equals(getAck())) && getType().equals(PacketType.JSON);
+    }
+
+    private boolean isEventAck() {
+        return ACK_DATA.equals(getAck()) && getType().equals(PacketType.EVENT);
+    }
+
     public boolean isAck() {
-        return getId() != null && !ACK_DATA.equals(getAck());
+        return getId() != null && (isEventAck() || isJsonAck());
     }
 
 }