はじめてのGlassfishで、はじめてのWebSocket。

Echo.java

import java.io.IOException;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
import javax.websocket.Session;
import javax.websocket.WebSocketClose;
import javax.websocket.WebSocketEndpoint;
import javax.websocket.WebSocketMessage;
import javax.websocket.WebSocketOpen;

/**
*
* @author sada
*/
@WebSocketEndpoint("/echo")
public class Echo {

  private static Set<Session> sessions = Collections.synchronizedSet(new HashSet<Session>());

  @WebSocketOpen
  public void open(Session session){
    System.out.println(session + " open!!!");
    sessions.add(session);
  }

  @WebSocketMessage
  public void say(String message, Session session) throws IOException{
    System.out.println(session + " " + message);
    for(Session s : sessions){
      if(s.isActive()){
        s.getRemote().sendString(s + " " + message);
      }else{
        System.out.println(s + " is not Active.");
        sessions.remove(s);
      }
    }
  }

  @WebSocketClose
  public void close(Session session){
    System.out.println("close!!!");
  }

}