org.emmanuel.spring.chat.handlers.EchoMessageHandler.java Source code

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Here is the source code for org.emmanuel.spring.chat.handlers.EchoMessageHandler.java

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package org.emmanuel.spring.chat.handlers;

import java.util.Map;
import java.util.Map.Entry;
import java.util.concurrent.ConcurrentHashMap;
import org.springframework.web.socket.CloseStatus;
import org.springframework.web.socket.TextMessage;
import org.springframework.web.socket.WebSocketSession;
import org.springframework.web.socket.handler.TextWebSocketHandler;

/**
 *
 * @author u329022
 */
public class EchoMessageHandler extends TextWebSocketHandler {

    private Map<String, WebSocketSession> sessions;

    public EchoMessageHandler() {
        sessions = new ConcurrentHashMap<String, WebSocketSession>();
    }

    /**
     * Invoked after WebSocket negotiation has succeeded and the WebSocket
     * connection is opened and ready for use.
     *
     * @throws Exception this method can handle or propagate exceptions; see
     * class-level Javadoc for details.
     `
     */
    public void OnOpen(WebSocketSession wss) throws Exception {
        if (!sessions.containsKey(wss.getId())) {
            sessions.put(wss.getId(), wss);
        }
    }

    /**
     * Invoked after the WebSocket connection has been closed by either side, or
     * after a transport error has occurred. Although the session may
     * technically still be open, depending on the underlying implementation,
     * sending messages at this point is discouraged and most likely will not
     * succeed.
     *
     * @throws Exception this method can handle or propagate exceptions; see
     * class-level Javadoc for details.
     */
    public void onClose(WebSocketSession wss, CloseStatus status) throws Exception {
        //sessions.remove(wss.getId());
        for (Entry<String, WebSocketSession> entry : this.sessions.entrySet()) {
            sessions.remove(entry.getKey());
        }
    }

    /**
     * Invoked when a new WebSocket message arrives.
     *
     * @throws Exception this method can handle or propagate exceptions; see
     * class-level Javadoc for details.
     */
    public void onMessage(WebSocketSession wss, TextMessage message) throws Exception {
        //wss.sendMessage(message);
        for (Entry<String, WebSocketSession> entry : this.sessions.entrySet()) {
            entry.getValue().sendMessage(message);
        }
    }

    /**
     * Handle an error from the underlying WebSocket message transport.
     *
     * @throws Exception this method can handle or propagate exceptions; see
     * class-level Javadoc for details.
     */
    public void onError(WebSocketSession session, Throwable exception) throws Exception {
    }
}