websocket学习

前台：
1、js包

<script src=".../sockjs.min.js"></script>  ``<script src=".../stomp.js"></script>

2、构造实例
var stompClient = Stomp.over(new SockJS(‘<%=request.getContextPath()%>/ws/sockjs?userid=userid’));
方法
(1).stompClient.ws.readyState属性返回实例对象的当前状态，共有四种。
0，表示正在连接。
1，表示连接成功，可以通信了。
2，表示连接正在关闭。
3，表示连接已经关闭，或者打开连接失败。
(2)stompClient.ws.onopen
实例对象的onopen属性，用于指定连接成功后的回调函数。
(3)stompClient.ws.onclose
实例对象的onclose属性，用于指定连接关闭后的回调函数。
(4)stompClient.ws.onmessage
实例对象的onmessage属性，用于指定收到服务器数据后的回调函数。

stompClient.ws.onmessage=function(event){        var data=JSON.parse(event.data);//返回的数据};

后台：
1、配置连接

package com.neal.config.spring;import javax.annotation.Resource;import org.springframework.stereotype.Component;import org.springframework.web.servlet.config.annotation.EnableWebMvc;import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;import org.springframework.web.socket.config.annotation.EnableWebSocket;import org.springframework.web.socket.config.annotation.WebSocketConfigurer;import org.springframework.web.socket.config.annotation.WebSocketHandlerRegistry;@Component@EnableWebMvc@EnableWebSocketpublic class MyWebSocketConfig extends WebMvcConfigurerAdapter implements WebSocketConfigurer{    @Resource    private MyWebSocketHandler handler;//消息处理器    @Override    public void registerWebSocketHandlers(WebSocketHandlerRegistry registry){//        registry.addHandler(handler, "/ws").addInterceptors(new HandShake());//设置支持window自带的websocket        registry.addHandler(handler, "/ws/sockjs").addInterceptors(new HandShake()).withSockJS();//设置支持sockjs    }}

2、Interceptor拦截

package com.neal.config.spring;import java.util.Map;import org.springframework.http.server.ServletServerHttpRequest;import org.springframework.http.server.ServerHttpRequest;import org.springframework.http.server.ServerHttpResponse;import org.springframework.web.socket.WebSocketHandler;import org.springframework.web.socket.server.HandshakeInterceptor;public class HandShake implements HandshakeInterceptor{    @Override    public boolean beforeHandshake(ServerHttpRequest request,ServerHttpResponse response,WebSocketHandler wsHandler,            Map<String, Object> attributes) throws Exception{        System.out.println("websocket开始握手");        String userid=((ServletServerHttpRequest) request).getServletRequest().getParameter("userid");        if(userid!=null){            attributes.put("userid", userid);         }else {            return false;        }        return true;    }    @Override    public void afterHandshake(ServerHttpRequest arg0,ServerHttpResponse arg1,WebSocketHandler arg2,Exception arg3){        System.out.println("websocket握手结束");    }}

3、MyWebSocketHandler具体实现细节

import java.io.IOException;import java.util.HashMap;import java.util.Iterator;import java.util.Map;import java.util.Map.Entry;import org.apache.log4j.Logger;import org.springframework.beans.factory.annotation.Autowired;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;import com.google.gson.Gson;import com.google.gson.GsonBuilder;//import com.google.gson.GsonBuilder;@Componentpublic class MyWebSocketHandler implements WebSocketHandler{       private Logger log=Logger.getLogger(this.getClass());       @Autowired       private T_fault_logService t_fault_logService;       private Gson gson=new Gson();        //用于存储websocket会话       public static final Map<String, WebSocketSession> sessionMap;          static {              sessionMap = new HashMap<String, WebSocketSession>();          }     @Override    public void afterConnectionClosed(WebSocketSession session, CloseStatus closeStatus)throws Exception {        // TODO Auto-generated method stub          System.out.println("Websocket:" + session.getId() + "已经关闭");              Iterator<Entry<String, WebSocketSession>> it = sessionMap                      .entrySet().iterator();              // 移除Socket会话              while (it.hasNext()) {                  Entry<String, WebSocketSession> entry = it.next();                  if (entry.getValue().getId().equals(session.getId())) {                      sessionMap.remove(entry.getKey());                      System.out.println("Socket会话已经移除:用户ID" + entry.getKey());                      break;                  }              }      }    @Override    public void afterConnectionEstablished(WebSocketSession session)throws Exception {        System.out.println("websocket握手成功");        //sessionMap.put(session.getId(),session);//将session会话存储起来，不存到内存，则在消息推送和广播方法无法操作会话        String userid = (String) session.getAttributes().get("userid");          if (userid!= null) {            sessionMap.put(IdCreater.getUUID(), session);          }      }    @Override    public void handleMessage(WebSocketSession session, WebSocketMessage<?> message)throws Exception {        // TODO Auto-generated method stub        session.sendMessage(message);    }    @Override    public void handleTransportError(WebSocketSession session, Throwable exception)            throws Exception {        // TODO Auto-generated method stub        if (session.isOpen()) {              session.close();          }          Iterator<Entry<String, WebSocketSession>> it = sessionMap                  .entrySet().iterator();          // 移除Socket会话          while (it.hasNext()) {              Entry<String, WebSocketSession> entry = it.next();              if (entry.getValue().getId().equals(session.getId())) {                  sessionMap.remove(entry.getKey());                  System.out.println("Socket会话已经移除:用户ID" + entry.getKey());                  break;              }          }           }    @Override    public boolean supportsPartialMessages() {        // TODO Auto-generated method stub        return false;    }    public void sendFaultNum1() throws IOException {          Iterator<Entry<String, WebSocketSession>> it = sessionMap.entrySet().iterator();          // 多线程群发          while (it.hasNext()) {              final Entry<String, WebSocketSession> entry = it.next();              if (entry.getValue().isOpen()) {                  new Thread(new Runnable() {                      public void run() {                          try {                              if (entry.getValue().isOpen()) {                                  entry.getValue().sendMessage("返回信息");                              }                          } catch (IOException e) {                              e.printStackTrace();                          }                      }                  }).start();              }          }      }     // 依次发送，也可以单个启用线程多线发送，但是为了省资源，依次发送    public void sendFaultNum2(){        try {            Iterator<Entry<String, WebSocketSession>> it = sessionMap.entrySet().iterator();             while (it.hasNext()) {                  if (entry.getValue().isOpen()) {                      try {                        entry.getValue().sendMessage(new TextMessage("返回信息"));                    } catch (IOException e) {                        e.printStackTrace();                    }                  }              }         } catch (Exception e) {            log.error(e.getMessage(), e);        }    }}

4、服务器开线程监听

import org.apache.log4j.Logger;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.context.ApplicationListener;import org.springframework.context.event.ContextRefreshedEvent;import org.springframework.stereotype.Component;import com.neal.config.spring.MyWebSocketHandler;@Componentpublic class PushTask implements ApplicationListener<ContextRefreshedEvent>{    private Logger log=Logger.getLogger(PushTask.class);    @Autowired    private MyWebSocketHandler myWebSocketHandler;    @Override    public void onApplicationEvent(ContextRefreshedEvent event) {        if(event.getApplicationContext().getParent()!=null){            Thread t=new Thread(new Runnable() {                @Override                public void run() {                    while(true){                        try{                            //myWebSocketHandler.sendFaultNum1();                            myWebSocketHandler.sendFaultNum2();                            Thread.sleep(1000);                        }catch (InterruptedException e) {                            e.printStackTrace();                            log.error(e.getMessage(), e);                        }                    }                }            });            t.start();        }    }}