Added methods for broadcasting messages (excluding sockets), custom data storing inside a socket and checking the room for emptiness

socket.io-server/src/main/java/io/socket/socketio/server/SocketIoAdapter.java

@@ -105,4 +105,13 @@ public void broadcast(Packet<?> packet, String[] rooms) throws IllegalArgumentEx
      * @throws IllegalArgumentException If socket is null.
      */
     public abstract String[] listClientRooms(SocketIoSocket socket) throws IllegalArgumentException;
+
+    /**
+     * Check whether room is empty
+     *
+     * @param room Room name to list sockets in.
+     * @return boolean whether room is empty
+     * @throws IllegalArgumentException If room is null.
+     */
+    public abstract boolean isEmptyRoom(String room) throws IllegalArgumentException;
 }

socket.io-server/src/main/java/io/socket/socketio/server/SocketIoMemoryAdapter.java

@@ -139,4 +139,14 @@ public String[] listClientRooms(SocketIoSocket socket) throws IllegalArgumentExc
             return new String[0];
         }
     }
+
+	@Override
+	public boolean isEmptyRoom(String room) throws IllegalArgumentException {
+		if (room == null) {
+			throw new IllegalArgumentException("room must not be null.");
+		}
+
+		Set<SocketIoSocket> socketsInRoom = mRoomSockets.get(room);
+		return socketsInRoom == null || socketsInRoom.isEmpty();
+	}
 }

socket.io-server/src/main/java/io/socket/socketio/server/SocketIoNamespace.java

@@ -71,5 +71,17 @@ public final void broadcast(String room, String event, Object... args) throws Il
      */
     public abstract void broadcast(String[] rooms, String event, Object[] args) throws IllegalArgumentException;
 
+    /**
+     * Broadcast a message to all clients in this namespace that
+     * have joined specified rooms. Optionally, specify sockets to exclude from sending.
+     *
+     * @param rooms Rooms to send message to.
+     * @param event Name of event to raise on remote client.
+     * @param socketsExcluded List of sockets to exclude from sending or null.
+     * @param args Array of arguments to send. Supported types are: JSONObject, JSONArray, null
+     * @throws IllegalArgumentException If event is null or argument is not of supported type.
+     */
+    public abstract void broadcast(String[] rooms, String event, SocketIoSocket[] socketsExcluded, Object[] args) throws IllegalArgumentException;
+
     abstract Map<String, SocketIoSocket> getConnectedSockets();
 }

socket.io-server/src/main/java/io/socket/socketio/server/SocketIoNamespaceGroupImpl.java

@@ -2,9 +2,7 @@
 
 import io.socket.engineio.server.Emitter;
 
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.Map;
+import java.util.*;
 import java.util.concurrent.atomic.AtomicInteger;
 
 final class SocketIoNamespaceGroupImpl extends SocketIoNamespace {
@@ -24,6 +22,13 @@ public void broadcast(String[] rooms, String event, Object[] args) throws Illega
         }
     }
 
+    @Override
+    public void broadcast(String[] rooms, String event, SocketIoSocket[] socketsExcluded, Object[] args) throws IllegalArgumentException {
+        for (SocketIoNamespaceImpl namespace : mChildNamespaces) {
+            namespace.broadcast(rooms, event, socketsExcluded, args);
+        }
+    }
+
     @Override
     Map<String, SocketIoSocket> getConnectedSockets() {
         final Map<String, SocketIoSocket> sockets = new HashMap<>();

socket.io-server/src/main/java/io/socket/socketio/server/SocketIoNamespaceImpl.java

@@ -4,7 +4,9 @@
 import io.socket.socketio.server.parser.Packet;
 import io.socket.socketio.server.parser.Parser;
 
+import java.util.Arrays;
 import java.util.Map;
+import java.util.Objects;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.atomic.AtomicInteger;
 
@@ -32,6 +34,24 @@ public void broadcast(String[] rooms, String event, Object[] args) throws Illega
         mAdapter.broadcast(packet, rooms);
     }
 
+    @Override
+    public void broadcast(String[] rooms, String event, SocketIoSocket[] socketsExcluded, Object[] args) throws IllegalArgumentException {
+        if (event == null) {
+            throw new IllegalArgumentException("event cannot be null.");
+        }
+
+        final Packet packet = PacketUtils.createDataPacket(Parser.EVENT, event, args);
+
+        String[] socketsExcludedIds = socketsExcluded == null ? null :
+                Arrays.stream(socketsExcluded)
+                        .filter(Objects::nonNull)
+                        .map(SocketIoSocket::getId)
+                        .distinct()
+                        .toArray(String[]::new);
+
+        mAdapter.broadcast(packet, rooms, socketsExcludedIds);
+    }
+
     @Override
     Map<String, SocketIoSocket> getConnectedSockets() {
         return mConnectedSockets;

socket.io-server/src/main/java/io/socket/socketio/server/SocketIoSocket.java

@@ -72,6 +72,7 @@ public interface ReceivedByLocalAcknowledgementCallback {
     private final HashMap<Integer, ReceivedByRemoteAcknowledgementCallback> mAcknowledgementCallbacks = new HashMap<>();
 
     private boolean mConnected;
+    private Object customData;
 
     SocketIoSocket(SocketIoNamespaceImpl namespace, SocketIoClient client, Object connectData) {
         mNamespace = namespace;
@@ -184,6 +185,33 @@ public void broadcast(String[] rooms, String event, Object[] args) throws Illega
         mAdapter.broadcast(packet, rooms, new String[] { getId() });
     }
 
+    /**
+     * Broadcast a message to all clients in this namespace that
+     * have joined specified rooms. Optionally, specify sockets to exclude from sending.
+     *
+     * @param rooms Rooms to send message to.
+     * @param event Name of event to raise on remote client.
+     * @param socketsExcluded List of sockets to exclude from sending or null.
+     * @param args Array of arguments to send. Supported types are: JSONObject, JSONArray, null.
+     * @throws IllegalArgumentException If argument is not of supported type or socketsExcluded is null.
+     */
+    public void broadcast(String[] rooms, String event, SocketIoSocket[] socketsExcluded, Object[] args) throws IllegalArgumentException {
+        if (event == null) {
+            throw new IllegalArgumentException("event cannot be null.");
+        }
+
+        final Packet<?> packet = PacketUtils.createDataPacket(Parser.EVENT, event, args);
+
+	    String[] socketsExcludedIds = socketsExcluded == null ? null :
+			    Arrays.stream(socketsExcluded)
+			            .filter(Objects::nonNull)
+			            .map(SocketIoSocket::getId)
+			            .distinct()
+			            .toArray(String[]::new);
+
+	    mAdapter.broadcast(packet, rooms, socketsExcludedIds);
+    }
+
     /**
      * Send data to remote client.
      *
@@ -270,6 +298,20 @@ public synchronized void leaveAllRooms() {
         mRooms.clear();
     }
 
+    /**
+     * Set customData object.
+     */
+    public void setCustomData(Object customData) {
+        this.customData = customData;
+    }
+
+	/**
+     * Get customData object.
+     */
+    public Object getCustomData() {
+        return this.customData;
+    }
+
     /**
      * Register listener for all user events.
      *