Websocket

Jboot 内置了 Undertow 服务器，完美支持 websocket 功能， tomcat8 也是内置了对 websocket 的支持。

在使用 websocket 之前，需要添加如下配置：

  1. jboot.web.webSocketEndpoint=your-endpoint-class-name

例如：

  1. //多个 endpoint 用英文逗号（,） 隔开。
  2. jboot.web.webSocketEndpoint=io.jboot.test.websocket.WebsocketDemo

WebsocketDemo 的代码如下：

  1. package io.jboot.test.websocket;
  3. import javax.websocket.OnMessage;
  4. import javax.websocket.Session;
  5. import javax.websocket.server.ServerEndpoint;
  8. @ServerEndpoint("/myapp.ws")
  9. public class WebsocketDemo {
  11.     @OnMessage
  12.     public void message(String message, Session session) {
  13.         for (Session s : session.getOpenSessions()) {
  14.             System.out.println("receive : " + message);
  15.             s.getAsyncRemote().sendText(message);
  16.         }
  17.     }
  18. }

这里要注意：@ServerEndpoint("/myapp.ws") 中的内容 /myapp.ws 必须有后缀，后缀可以自定义，否则会被 JFinal 的拦截。

我们还需要写一个 Controller，来渲染 html 页面。

  1. @RequestMapping("/websocket")
  2. public class WebsocketController extends JbootController {
  4.     public void index() {
  5.         render("/websocket.html");
  6.     }
  8. }

websocket.html 的内容如下：

  1. <html>
  2. <head><title>Undertow Chat</title>
  3.     <script>
  4.         var socket;
  5.         if (window.WebSocket) {
  6.             // 这里的 /myapp.ws 必须和以上 @ServerEndpoint("/myapp.ws") 
  7.             // 中配置的内容保持一致
  8.             socket = new WebSocket("ws://127.0.0.1:8080/myapp.ws");
  9.             socket.onmessage = function (event) {
  10.                 var chat = document.getElementById('chat');
  11.                 chat.innerHTML = chat.innerHTML + event.data + "<br />";
  12.             };
  13.         } else {
  14.             alert("Your browser does not support Websockets. (Use Chrome)");
  15.         }
  17.         function send(message) {
  18.             if (!window.WebSocket) {
  19.                 return false;
  20.             }
  21.             if (socket.readyState == WebSocket.OPEN) {
  22.                 socket.send(message);
  23.             } else {
  24.                 alert("The socket is not open.");
  25.             }
  26.             return false;
  27.         }
  28.     </script>
  29.     <style type="text/css">
  30.         html,body {width:100%;height:100%;}
  31.         html,body,ul,ol,dl,li,dt,dd,p,blockquote,fieldset,legend,img,form,h1,h2,h3,h4,h5,h6 {margin:0;padding:0;}
  32.         body {
  33.             font:normal 12px/1.5 Arial,Helvetica,'Bitstream Vera Sans',sans-serif;
  34.             background: #c5deea; /* Old browsers */
  35.             background: -moz-linear-gradient(top, #c5deea 0%, #066dab 100%); /* FF3.6+ */
  36.             background: -webkit-gradient(linear, left top, left bottom, color-stop(0%, #c5deea), color-stop(100%, #066dab)); /* Chrome,Safari4+ */
  37.             background: -webkit-linear-gradient(top, #c5deea 0%, #066dab 100%); /* Chrome10+,Safari5.1+ */
  38.             background: -o-linear-gradient(top, #c5deea 0%, #066dab 100%); /* Opera 11.10+ */
  39.             background: -ms-linear-gradient(top, #c5deea 0%, #066dab 100%); /* IE10+ */
  40.             background: linear-gradient(to bottom, #c5deea 0%, #066dab 100%); /* W3C */
  41.             height: 90%;
  42.         }
  44.         .center {
  45.             margin-left: auto;
  46.             margin-right: auto;
  47.             width: 70%;
  48.             background: white;
  49.         }
  51.         .chatform {
  52.             margin-left: auto;
  53.             margin-right: auto;
  54.             margin-bottom: 0;
  55.             width: 70%;
  56.         }
  57.         form{
  58.             width: 100%;
  59.         }
  60.         label{
  61.             display: inline;
  62.             width: 100px;
  63.         }
  64.         #msg{
  65.             display: inline;
  66.             width: 100%;
  67.         }
  69.     </style>
  70. </head>
  71. <body>
  72. <div class="page">
  73.     <div class="center" >
  74.         <h1>JSR-356 Web Socket Chat</h1>
  75.         <div id="chat" style="height:100%;width: 100%; overflow: scroll;">
  78.         </div>
  80.         <form onsubmit="return false;" class="chatform" action="">
  81.             <label for="msg">Message</label>
  82.             <input type="text" name="message" id="msg"  
  83.             onkeypress="if(event.keyCode==13) { send(this.form.message.value); this.value='' } " />
  84.         </form>
  85.     </div>
  86. </div>
  87. </body>
  88. </html>