WebSockets production ready server in Java?

Question

EDIT: removed reference to C# as the only accepted answer is about Java. If someone needs information about websocket server implementation in C#, ask a new

Answer 1

JETTY

I've spent the past week mauling over how to make a WebSocket server. Finally got something to work hope this helps. It uses libraries from Jetty (jars).

File WebRTC_IceServer.java

package com.evanstools;
import org.eclipse.jetty.server.*;
import org.eclipse.jetty.websocket.server.*;
public class WebRTC_IceServer{
public static void main(String[] args){
try{
////////////////////////
if(args.length == 0){
  System.out.printf("%s%n","WebRTC_IceServer [port]");
  return;
}
Server server = new Server(Integer.parseInt(args[0]));
WebSocketHandler.Simple webSocketHandlerSimple = new WebSocketHandler.Simple(WebsocketPOJO.class);
server.setHandler(webSocketHandlerSimple);
server.start();
server.join();
////////////////////////
}catch(Exception w){w.printStackTrace();}
}
}

File WebsocketPOJO.java

package com.evanstools;
import org.eclipse.jetty.websocket.api.annotations.*;
import org.eclipse.jetty.websocket.api.Session;
//The class must be not abstract and public.
@WebSocket
public class WebsocketPOJO{
//Flags one method in the class as receiving the On Connect event.
//Method must be public, not abstract, return void, and have a single Session parameter.
@OnWebSocketConnect
public void onWebSocketConnect(Session session){
    System.out.printf("%s%n","test client connected");
}
//Flags one method in the class as receiving the On Close event.
//Method signature must be public, not abstract, and return void.
//The method parameters:
////Session (optional)
////int closeCode (required)
////String closeReason (required)
@OnWebSocketClose
public void OnWebSocketClose(Session session,int closeCode,String closeReason){}
//Flags up to 2 methods in the class as receiving On Message events.
//You can have 1 method for TEXT messages, and 1 method for BINARY messages.
//Method signature must be public, not abstract, and return void.
//The method parameters for Text messages:
////Session (optional)
////String text (required)
//The method parameters for Binary messages:
////Session (optional)
////byte buf[] (required)
////int offset (required)
////int length (required)
@OnWebSocketMessage
public void onWebSocketMessageString(Session session, String text){}
//Flags one method in the class as receiving Error events from the WebSocket implementation.
//Method signatures must be public, not abstract, and return void.
//The method parameters:
////Session (optional)
////Throwable cause (required)
//@OnWebSocketError
//Flags one method in the class as receiving Frame events from the WebSocket implementation after they have been processed by any extensions declared during the Upgrade handshake.
//Method signatures must be public, not abstract, and return void.
//The method parameters:
////Session (optional)
///Frame (required)
//The Frame received will be notified on this method, then be processed by Jetty, possibly resulting in another event, such as On Close, or On Message. Changes to the Frame will not be seen by Jetty.
//@OnWebSocketFrame
}