基于Tomcate、java、websocket 简单在线聊天

web.xml配置

跟所有servlet 在web.xml进行配置

<servlet>
		<servlet-name>socketHome</servlet-name>
		<servlet-class>SocketServer</servlet-class>
	</servlet>
	<servlet-mapping>
		<servlet-name>socketHome</servlet-name>
		<url-pattern>/ws</url-pattern>
	</servlet-mapping>

后台代码
SocketServer.java，ws://协议的请求就必须实现WebSocketServlet这个类

import java.util.concurrent.atomic.AtomicInteger;

import javax.servlet.http.HttpServletRequest;

import org.apache.catalina.websocket.StreamInbound;
import org.apache.catalina.websocket.WebSocketServlet;

/**
 * 
 * @author wangbg 通讯入口
 */
@SuppressWarnings("deprecation")
public class SocketServer extends WebSocketServlet {

	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;

	/**
	 * 生成/获取用户
	 * 
	 * @param reuqest
	 * @return
	 */
	private String getUser(HttpServletRequest reuqest) {
		Object objectUser = reuqest.getSession().getAttribute("user");
		if (objectUser == null) {
			objectUser = "游客" + reuqest.getSession().getId();
		}
		return objectUser.toString();
	}

	// 实现createWebSocketInbound，在这里初始化自定义的WebSocket连接对象
	@Override
	protected StreamInbound createWebSocketInbound(String arg0,
			HttpServletRequest reuqest) {
		// TODO Auto-generated method stub
		return new MessageInbound(getUser(reuqest));
	}
}

MessageInbound.java,WebSocket连接对象类
代码中的主要实现了onOpen、onTextMessage方法，分别处理用户上线、发送消息,还有onClose方法 不过我没有实现。

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;

import net.sf.json.JSONObject;

import org.apache.catalina.websocket.WsOutbound;


/**
 * 
 * @author wangbg 通訊交互
 */
@SuppressWarnings("deprecation")
public class MessageInbound extends
		org.apache.catalina.websocket.MessageInbound {

	private final String user;

	public MessageInbound(String user) {
		// TODO Auto-generated constructor stub
		this.user = user;
	}

	public String getUser() {
		return this.user;
	}

	/**
	 * 用户连接触发事件 1 向连接池添加当前用户 2 向在线用户发送当前用户上线消息 3 向当前用户发送在线用户列表
	 */
	@Override
	protected void onOpen(WsOutbound outbound) {
		// TODO Auto-generated method stub
		super.onOpen(outbound);
		// 向连接池添加当前用户
		InboundPool.addInbound(this);
		JSONObject result = new JSONObject();
		// 向在线用户发送当前用户上线消息
		InboundPool.sendMessage(this.user + "上线");
		// 向当前用户发送在线用户列表
		result = new JSONObject();
		result.element("onlineUser", InboundPool.getOnlineUser());
		InboundPool.sendMessageToUser(this.user, result.toString());
	}

	@Override
	protected void onBinaryMessage(ByteBuffer arg0) throws IOException {
		// TODO Auto-generated method stub

	}

	/**
	 * 客户端发送消息时触发
	 */
	@Override
	protected void onTextMessage(CharBuffer message) throws IOException {
		// TODO Auto-generated method stub
		InboundPool.sendMessage(this.user + ":" + message.toString());
	}

}

InboundPool.java,连接对象池，管理在线用户的连接

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;

import net.sf.json.JSONObject;

import org.apache.catalina.websocket.WsOutbound;

/**
 * 
 * @author wangbg 通訊交互
 */
@SuppressWarnings("deprecation")
public class MessageInbound extends
		org.apache.catalina.websocket.MessageInbound {

	private final String user;

	public MessageInbound(String user) {
		// TODO Auto-generated constructor stub
		this.user = user;
	}

	public String getUser() {
		return this.user;
	}

	/**
	 * 用户连接触发事件 1 向连接池添加当前用户 2 向在线用户发送当前用户上线消息 3 向当前用户发送在线用户列表
	 */
	@Override
	protected void onOpen(WsOutbound outbound) {
		// TODO Auto-generated method stub
		super.onOpen(outbound);
		// 向连接池添加当前用户
		InboundPool.addInbound(this);
		JSONObject result = new JSONObject();
		// 向在线用户发送当前用户上线消息
		InboundPool.sendMessage(this.user + "上线");
		// 向当前用户发送在线用户列表
		result = new JSONObject();
		result.element("onlineUser", InboundPool.getOnlineUser());
		InboundPool.sendMessageToUser(this.user, result.toString());
	}

	@Override
	protected void onBinaryMessage(ByteBuffer arg0) throws IOException {
		// TODO Auto-generated method stub

	}

	/**
	 * 客户端发送消息时触发
	 */
	@Override
	protected void onTextMessage(CharBuffer message) throws IOException {
		// TODO Auto-generated method stub
		InboundPool.sendMessage(this.user + ":" + message.toString());
	}

}

index.jsp 页面访问及交互

<%@ page language="java" contentType="text/html; charset=UTF-8"
	pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<body>
	<input type="text" id="message" size="60" />
	<input type="button" id="send" value="发送" />
	<br>
	<div id="panel"></div>
</body>
<script type="text/javascript">
	var panel = document.getElementById('panel');  
	var message = document.getElementById('message');  
	var send = document.getElementById('send') 
	// 控制台输出对象  
	var console = {
		log : function(text) {
			panel.innerHTML += text + "<br>";
		}
	};
	// WebSocket
	var socketBox = {
		socket : null, // WebSocket连接对象  
		host : '', // WebSocket连接 url  
		connect : function() { // 连接服务器  
			window.WebSocket = window.WebSocket || window.MozWebSocket;
			if (!window.WebSocket) { // 检测浏览器支持  
				console.log('Error: 请升级到ie10+浏览器 .');
				return;
			}
			// 创建连接并注册响应函数  
			this.socket = new WebSocket(this.host);
			this.socket.onopen = function() {
				console.log("连接服务器.");
			};
			this.socket.onmessage = function(res) {
				if (res.type == "message") {
					console.log(res.data);
				}
			};
			this.socket.onclose = function() {
				console.log("服务器断开 .");
				socketBox.socket.onclose();
				socketBox.socket = null; // 清理  
			};
		},
		send : function(message) { // 发送消息方法  
			if (this.socket) {
				this.socket.send(message);
				return true;
			}
			console.log('请先连接服务器 !!!');
			return false;
		}
	};
	// 初始化WebSocket连接 url  
	socketBox.host = (window.location.protocol == 'http:') ? 'ws://' : 'wss://';
	socketBox.host += window.location.host + '/websocket/ws';
	// 初始化按钮点击事件函数  
	send.onclick = function() {
		var ms = message.value;
		if (!ms)
			return;
		if (!socketBox.send(ms))
			return;
		message.value = '';
	};
	if (!socketBox.socket)
		socketBox.connect();
</script>
</body>
</html>