manzke/TailorWebSocketServlet.java

## TailorWebSocketServlet.java
package de.devsurf.html.tail;

import java.io.IOException;
import java.util.Date;
import java.util.Set;
import java.util.concurrent.CopyOnWriteArraySet;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.eclipse.jetty.websocket.WebSocket;
import org.eclipse.jetty.websocket.WebSocketServlet;

public class TailorWebSocketServlet extends WebSocketServlet {
	private static final long serialVersionUID = -7289719281366784056L;
	public static String newLine = System.getProperty("line.separator");

	private final Set<TailorSocket> _members = new CopyOnWriteArraySet<TailorSocket>();
	private ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor();

	@Override
	public void init() throws ServletException {
		super.init();
		executor.scheduleAtFixedRate(new Runnable() {
			@Override
			public void run() {
				System.out.println("Running Server Message Sending");
				for(TailorSocket member : _members){
					System.out.println("Trying to send to Member!");
					if(member.isOpen()){
						System.out.println("Sending!");
						try {
							member.sendMessage("Sending a Message to you Guys! "+new Date()+newLine);
						} catch (IOException e) {
							e.printStackTrace();
						}
					}
				}
			}
		}, 2, 2, TimeUnit.SECONDS);

	}

	protected void doGet(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		getServletContext().getNamedDispatcher("default").forward(request,
				response);
	}

	public WebSocket doWebSocketConnect(HttpServletRequest request,
			String protocol) {
		return new TailorSocket();
	}

	class TailorSocket implements WebSocket.OnTextMessage {
		private Connection _connection;

		@Override
		public void onClose(int closeCode, String message) {
			_members.remove(this);
		}

		public void sendMessage(String data) throws IOException {
			_connection.sendMessage(data);
		}

		@Override
		public void onMessage(String data) {
			System.out.println("Received: "+data);
		}

		public boolean isOpen() {
			return _connection.isOpen();
		}

		@Override
		public void onOpen(Connection connection) {
			_members.add(this);
			_connection = connection;
			try {
				connection.sendMessage("Server received Web Socket upgrade and added it to Receiver List.");
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}
}

## test.html
<html>
	<head>
		<title>Tail-based by Web Sockets</title>
		<script type='text/javascript'>
			if (!window.WebSocket)
				alert("WebSocket not supported by this browser");

			function $() {
				return document.getElementById(arguments[0]);
			}
			function $F() {
				return document.getElementById(arguments[0]).value;
			}

			function getKeyCode(ev) {
				if (window.event)
					return window.event.keyCode;
				return ev.keyCode;
			}

			var server = {
				connect : function() {
					var location = document.location.toString().replace('http://',
							'ws://').replace('https://', 'wss://').replace('test.html','servlet/WebSocket');
							alert(location);
					this._ws = new WebSocket(location);
					this._ws.onopen = this._onopen;
					this._ws.onmessage = this._onmessage;
					this._ws.onclose = this._onclose;
				},

				_onopen : function() {
					server._send('websockets are open for communications!');
				},

				_send : function(message) {
					if (this._ws)
						this._ws.send(message);
				},

				send : function(text) {
					if (text != null && text.length > 0)
						server._send(text);
				},

				_onmessage : function(m) {
					if (m.data) {
						var messageBox = $('messageBox');
						var spanText = document.createElement('span');
						spanText.className = 'text';
						spanText.innerHTML = m.data;
						var lineBreak = document.createElement('br');
						messageBox.appendChild(spanText);
						messageBox.appendChild(lineBreak);
						messageBox.scrollTop = messageBox.scrollHeight
								- messageBox.clientHeight;
					}
				},

				_onclose : function(m) {
					this._ws = null;
				}
			};
		</script>
		<style type='text/css'>
			div {
				border: 0px solid black;
			}

			div#messageBox {
				clear: both;
				width: 40em;
				height: 20ex;
				overflow: auto;
				background-color: #f0f0f0;
				padding: 4px;
				border: 1px solid black;
			}

			div#input {
				clear: both;
				width: 40em;
				padding: 4px;
				background-color: #e0e0e0;
				border: 1px solid black;
				border-top: 0px
			}

			div.hidden {
				display: none;
			}

			span.alert {
				font-style: italic;
			}
		</style>
	</head>
	<body>
		<div id='messageBox'></div>
		<div id='input'>
			<div>
				<input id='connect' class='button' type='submit' name='Connect'
					value='Connect' />
			</div>
		</div>
		<script type='text/javascript'>
			$('connect').onclick = function(event) {
				server.connect();
				return false;
			};
		</script>

		<p>
			This is a demonstration of the Jetty websocket server.
		</p>
	</body>
</html>

## web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
	http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
	<display-name>tailor</display-name>
	<servlet>
		<servlet-name>WebSocket</servlet-name>
		<servlet-class>de.devsurf.html.tail.TailorWebSocketServlet</servlet-class>
	</servlet>
	<servlet-mapping>
		<servlet-name>WebSocket</servlet-name>
		<url-pattern>/servlet/*</url-pattern>
	</servlet-mapping>

	<welcome-file-list>
		<welcome-file>test.html</welcome-file>
	</welcome-file-list>
</web-app>
	package de.devsurf.html.tail;

	import java.io.IOException;
	import java.util.Date;
	import java.util.Set;
	import java.util.concurrent.CopyOnWriteArraySet;
	import java.util.concurrent.Executors;
	import java.util.concurrent.ScheduledExecutorService;
	import java.util.concurrent.TimeUnit;

	import javax.servlet.ServletException;
	import javax.servlet.http.HttpServletRequest;
	import javax.servlet.http.HttpServletResponse;

	import org.eclipse.jetty.websocket.WebSocket;
	import org.eclipse.jetty.websocket.WebSocketServlet;

	public class TailorWebSocketServlet extends WebSocketServlet {
	private static final long serialVersionUID = -7289719281366784056L;
	public static String newLine = System.getProperty("line.separator");

	private final Set<TailorSocket> _members = new CopyOnWriteArraySet<TailorSocket>();
	private ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor();

	@Override
	public void init() throws ServletException {
	super.init();
	executor.scheduleAtFixedRate(new Runnable() {
	@Override
	public void run() {
	System.out.println("Running Server Message Sending");
	for(TailorSocket member : _members){
	System.out.println("Trying to send to Member!");
	if(member.isOpen()){
	System.out.println("Sending!");
	try {
	member.sendMessage("Sending a Message to you Guys! "+new Date()+newLine);
	} catch (IOException e) {
	e.printStackTrace();
	}
	}
	}
	}
	}, 2, 2, TimeUnit.SECONDS);

	}

	protected void doGet(HttpServletRequest request,
	HttpServletResponse response) throws ServletException, IOException {
	getServletContext().getNamedDispatcher("default").forward(request,
	response);
	}

	public WebSocket doWebSocketConnect(HttpServletRequest request,
	String protocol) {
	return new TailorSocket();
	}

	class TailorSocket implements WebSocket.OnTextMessage {
	private Connection _connection;

	@Override
	public void onClose(int closeCode, String message) {
	_members.remove(this);
	}

	public void sendMessage(String data) throws IOException {
	_connection.sendMessage(data);
	}

	@Override
	public void onMessage(String data) {
	System.out.println("Received: "+data);
	}

	public boolean isOpen() {
	return _connection.isOpen();
	}

	@Override
	public void onOpen(Connection connection) {
	_members.add(this);
	_connection = connection;
	try {
	connection.sendMessage("Server received Web Socket upgrade and added it to Receiver List.");
	} catch (IOException e) {
	e.printStackTrace();
	}
	}
	}
	}
	<html>
	<head>
	<title>Tail-based by Web Sockets</title>
	<script type='text/javascript'>
	if (!window.WebSocket)
	alert("WebSocket not supported by this browser");

	function $() {
	return document.getElementById(arguments[0]);
	}
	function $F() {
	return document.getElementById(arguments[0]).value;
	}

	function getKeyCode(ev) {
	if (window.event)
	return window.event.keyCode;
	return ev.keyCode;
	}

	var server = {
	connect : function() {
	var location = document.location.toString().replace('http://',
	'ws://').replace('https://', 'wss://').replace('test.html','servlet/WebSocket');
	alert(location);
	this._ws = new WebSocket(location);
	this._ws.onopen = this._onopen;
	this._ws.onmessage = this._onmessage;
	this._ws.onclose = this._onclose;
	},

	_onopen : function() {
	server._send('websockets are open for communications!');
	},

	_send : function(message) {
	if (this._ws)
	this._ws.send(message);
	},

	send : function(text) {
	if (text != null && text.length > 0)
	server._send(text);
	},

	_onmessage : function(m) {
	if (m.data) {
	var messageBox = $('messageBox');
	var spanText = document.createElement('span');
	spanText.className = 'text';
	spanText.innerHTML = m.data;
	var lineBreak = document.createElement('br');
	messageBox.appendChild(spanText);
	messageBox.appendChild(lineBreak);
	messageBox.scrollTop = messageBox.scrollHeight
	- messageBox.clientHeight;
	}
	},

	_onclose : function(m) {
	this._ws = null;
	}
	};
	</script>
	<style type='text/css'>
	div {
	border: 0px solid black;
	}

	div#messageBox {
	clear: both;
	width: 40em;
	height: 20ex;
	overflow: auto;
	background-color: #f0f0f0;
	padding: 4px;
	border: 1px solid black;
	}

	div#input {
	clear: both;
	width: 40em;
	padding: 4px;
	background-color: #e0e0e0;
	border: 1px solid black;
	border-top: 0px
	}

	div.hidden {
	display: none;
	}

	span.alert {
	font-style: italic;
	}
	</style>
	</head>
	<body>
	<div id='messageBox'></div>
	<div id='input'>
	<div>
	<input id='connect' class='button' type='submit' name='Connect'
	value='Connect' />
	</div>
	</div>
	<script type='text/javascript'>
	$('connect').onclick = function(event) {
	server.connect();
	return false;
	};
	</script>

	<p>
	This is a demonstration of the Jetty websocket server.
	</p>
	</body>
	</html>
	<?xml version="1.0" encoding="UTF-8"?>
	<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
	http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
	<display-name>tailor</display-name>
	<servlet>
	<servlet-name>WebSocket</servlet-name>
	<servlet-class>de.devsurf.html.tail.TailorWebSocketServlet</servlet-class>
	</servlet>
	<servlet-mapping>
	<servlet-name>WebSocket</servlet-name>
	<url-pattern>/servlet/*</url-pattern>
	</servlet-mapping>

	<welcome-file-list>
	<welcome-file>test.html</welcome-file>
	</welcome-file-list>
	</web-app>