Support default event listener

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

@@ -251,7 +251,6 @@ public <T> void addEventListener(String eventName, Class<T> eventClass, DataList
     @Override
     public void addEventInterceptor(EventInterceptor eventInterceptor) {
         mainNamespace.addEventInterceptor(eventInterceptor);
-
     }
 
 
@@ -260,6 +259,11 @@ public void removeAllListeners(String eventName) {
         mainNamespace.removeAllListeners(eventName);
     }
 
+    @Override
+    public <T> void setDefaultListener(Class<T> eventClass, DefaultDataListener<T> listener) {
+        mainNamespace.setDefaultListener(eventClass,listener);
+    }
+
     @Override
     public void addDisconnectListener(DisconnectListener listener) {
         mainNamespace.addDisconnectListener(listener);

src/main/java/com/corundumstudio/socketio/listener/ClientListeners.java

@@ -35,5 +35,7 @@ public interface ClientListeners {
     void addListeners(Object listeners, Class<?> listenersClass);
 
     void removeAllListeners(String eventName);
+
+    <T> void setDefaultListener(Class<T> eventClass, DefaultDataListener<T> listener);
 
 }

src/main/java/com/corundumstudio/socketio/listener/DefaultDataListener.java

@@ -0,0 +1,34 @@
+/**
+ * Copyright (c) 2012-2019 Nikita Koksharov
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.corundumstudio.socketio.listener;
+
+import com.corundumstudio.socketio.AckRequest;
+import com.corundumstudio.socketio.SocketIOClient;
+
+public interface DefaultDataListener<T> {
+
+    /**
+     * Invokes when data object received from client
+     *
+     * @param client - receiver
+     * @param data - received object
+     * @param ackSender - ack request
+     * @param eventName - event name
+     *
+     */
+    void onData(SocketIOClient client, T data, AckRequest ackSender,String eventName) throws Exception;
+
+}

src/main/java/com/corundumstudio/socketio/namespace/EventEntry.java

@@ -19,9 +19,11 @@
 import java.util.concurrent.ConcurrentLinkedQueue;
 
 import com.corundumstudio.socketio.listener.DataListener;
+import com.corundumstudio.socketio.listener.DefaultDataListener;
 
 public class EventEntry<T> {
 
+
     private final Queue<DataListener<T>> listeners = new ConcurrentLinkedQueue<DataListener<T>>();;
 
     public EventEntry() {
@@ -36,4 +38,14 @@ public Queue<DataListener<T>> getListeners() {
         return listeners;
     }
 
+    private DefaultDataListener defaultDataListener;
+
+    public void setDefaultDataListener(DefaultDataListener defaultDataListener){
+        this.defaultDataListener=defaultDataListener;
+    }
+
+    public DefaultDataListener getDefaultDataListener(){
+        return defaultDataListener;
+    }
+
 }

src/main/java/com/corundumstudio/socketio/namespace/Namespace.java

@@ -56,6 +56,8 @@ public class Namespace implements SocketIONamespace {
     public static final String DEFAULT_NAME = "";
 
     private final ScannerEngine engine = new ScannerEngine();
+
+    private  EventEntry<?> defaultEventListener;
     private final ConcurrentMap<String, EventEntry<?>> eventListeners = PlatformDependent.newConcurrentHashMap();
     private final Queue<ConnectListener> connectListeners = new ConcurrentLinkedQueue<ConnectListener>();
     private final Queue<DisconnectListener> disconnectListeners = new ConcurrentLinkedQueue<DisconnectListener>();
@@ -113,6 +115,14 @@ public void removeAllListeners(String eventName) {
         }
     }
 
+    @Override
+    public <T> void setDefaultListener(Class<T> eventClass, DefaultDataListener<T> listener) {
+        EventEntry entry = new EventEntry<T>();
+        entry.setDefaultDataListener(listener);
+        defaultEventListener = entry;
+    }
+
+
     @Override
     @SuppressWarnings({"unchecked", "rawtypes"})
     public <T> void addEventListener(String eventName, Class<T> eventClass, DataListener<T> listener) {
@@ -137,6 +147,20 @@ public void addEventInterceptor(EventInterceptor eventInterceptor) {
     public void onEvent(NamespaceClient client, String eventName, List<Object> args, AckRequest ackRequest) {
         EventEntry entry = eventListeners.get(eventName);
         if (entry == null) {
+            if(defaultEventListener!=null && defaultEventListener.getDefaultDataListener()!=null){
+                try {
+                    Object data = null;
+                    if(!args.isEmpty()){
+                        data = args.get(0);
+                    }
+                    defaultEventListener.getDefaultDataListener().onData(client, data, ackRequest,eventName);
+                } catch (Exception e) {
+                    exceptionListener.onEventException(e, args, client);
+                    if (ackMode == AckMode.AUTO_SUCCESS_ONLY) {
+                        return;
+                    }
+                }
+            }
             return;
         }