爱威尔-spring mvc4.X+Websocket 实现实时消息推送--已开源例子

关于原理我就不啰嗦了。自己在网上搜一下就知道了。


	应广大网友要求，已开源一个例子更参考：http://git.oschina.net/weir/spring_websocket


	1.注册服务：


	 

<pre class="prettyprint lang-java">package com.tw.webSocket;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
import org.springframework.web.socket.WebSocketHandler;
import org.springframework.web.socket.config.annotation.EnableWebSocket;
import org.springframework.web.socket.config.annotation.WebSocketConfigurer;
import org.springframework.web.socket.config.annotation.WebSocketHandlerRegistry;

@Configuration
@EnableWebSocket
public class WebSocketConfig extends WebMvcConfigurerAdapter implements WebSocketConfigurer{

@Override
	public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
		registry.addHandler(systemWebSocketHandler(), "/webSocketServer").addInterceptors(new MyHandshakeInterceptor());
		System.out.println("registed!");
		registry.addHandler(systemWebSocketHandler(), "/sockjs/webSocketServer").addInterceptors(new MyHandshakeInterceptor()).withSockJS();
		
	}
	@Bean
	public WebSocketHandler systemWebSocketHandler(){
		return new SystemWebSocketHandler();
	}
}
</pre>
我们注册两种：ws 和http 实现websocket。

	 


	2.继承握手拦截器：


	 

<pre class="prettyprint lang-java">package com.tw.webSocket;

import java.util.Map;

import javax.servlet.http.HttpSession;

import org.springframework.http.server.ServerHttpRequest;
import org.springframework.http.server.ServerHttpResponse;
import org.springframework.http.server.ServletServerHttpRequest;
import org.springframework.stereotype.Component;
import org.springframework.web.socket.WebSocketHandler;
import org.springframework.web.socket.server.support.HttpSessionHandshakeInterceptor;

import com.tw.entity.sys.User;

@Component
public class MyHandshakeInterceptor extends HttpSessionHandshakeInterceptor{

@Override
	public boolean beforeHandshake(ServerHttpRequest request,
			ServerHttpResponse response, WebSocketHandler handler,
			Map<string, object=""> map) throws Exception {
		if (request instanceof ServletServerHttpRequest) {
			ServletServerHttpRequest servletRequest = (ServletServerHttpRequest) request;
			HttpSession session = servletRequest.getServletRequest().getSession(false);
			if (session!=null) {
				System.out.println("ok");
				User u = (User) session.getAttribute("U");
				map.put("username", u.getName());
			}
		}
		return true;
	}
	
	@Override
	public void afterHandshake(ServerHttpRequest request,
			ServerHttpResponse response, WebSocketHandler wsHandler,
			Exception ex) {
	}
}
</string,></pre>
这里是拿到在线的用户。

	 


	3.实现服务端的消息接受和推送：


	 

<pre class="prettyprint lang-java">package com.tw.webSocket;

import java.io.IOException;
import java.util.ArrayList;

import org.springframework.stereotype.Component;
import org.springframework.web.socket.CloseStatus;
import org.springframework.web.socket.TextMessage;
import org.springframework.web.socket.WebSocketHandler;
import org.springframework.web.socket.WebSocketMessage;
import org.springframework.web.socket.WebSocketSession;
@Component
public class SystemWebSocketHandler implements WebSocketHandler{

private static final ArrayListusers;
	static{
		users = new ArrayList();
	}
	
	public SystemWebSocketHandler(){
		
	}
	@Override
	public void afterConnectionClosed(WebSocketSession session, CloseStatus status)
			throws Exception {
		users.remove(session);
	}

@Override
	public void afterConnectionEstablished(WebSocketSession session)
			throws Exception {
		System.out.println("Server:cennected OK!");
		users.add(session);
	}

@Override
	public void handleMessage(WebSocketSession session, WebSocketMessage message)
			throws Exception {
		TextMessage tm = new TextMessage(message.getPayload()+"");
		System.out.println(message.getPayload());
		session.sendMessage(tm);
	}

@Override
	public void handleTransportError(WebSocketSession session, Throwable throwable)
			throws Exception {
		if (session.isOpen()) {
			session.close();
		}
		users.remove(session);
	}

@Override
	public boolean supportsPartialMessages() {
		return false;
	}

/**
	 * 给所有在线用户发送消息
	 * @param message
	 */
	public void sendMessageToUsers(TextMessage message) {
		for (WebSocketSession user : users) {
			if (user.isOpen()) {
				try {
					user.sendMessage(message);
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
	}
	
	public void sendMessageToUser(String username,TextMessage message) {
		for (WebSocketSession user : users) {
			if (user.getAttributes().get("username").equals(username)) {
				try {
					if (user.isOpen()) {
						user.sendMessage(message);
					}
				} catch (IOException e) {
					e.printStackTrace();
				}
				break;
			}
		}
	}
}
</pre>
4.配置文件applicationContext.xml：

	 


	没有变动。


	 


	4.2 tw-servlet.xml：


	 

这里就加了个：xmlns:websocket="http://www.springframework.org/schema/websocket"

	 


	http://www.springframework.org/schema/websocket http://www.springframework.org/schema/websocket/spring-websocket-4.1.xsd


	 


	4.3 web.xml 没有任何特殊的。


	 


	5.在需要显示消息的页面这样做：


	 


	 

<pre class="prettyprint lang-html"><%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>Java API for WebSocket (JSR-356)请输入：发送</pre>

	 


	 

<pre class="prettyprint lang-html"><%@ page language="java" pageEncoding="UTF-8"%>
hi交流： </pre>

	 


	 

6.在controller里面就可以这样调用了：

	 


	 


	 

<pre class="prettyprint lang-java">@Bean
	public SystemWebSocketHandler systemWebSocketHandler(){
		return new SystemWebSocketHandler();
	}
	
	@RequestMapping("/auditing")
 @ResponseBody
 public String auditing(HttpServletRequest request){
 //无关代码都省略了
 systemWebSocketHandler().sendMessageToUser("admin", new TextMessage("你好"));
 return "";
 }</pre>

	 


	这些代码就可以放在自己需要的任何地方了。


	基本就这样了，你想做web聊天室 或  web的网页消息提示都可以。