WebSocket JavaScript API(client)

<script>
    var URL = "ws://localhost:8080/WebSocketChatRoom/chatRoomServer";
    var websocket;
    var userName;

    function setConnected(connected) {
        document.getElementById(‘connect‘).disabled=connected;
        document.getElementById(‘disconnect‘).disabled = !connected;
        document.getElementById(‘send‘).disabled = !connected;
    }

    function connect() {

        if(‘WebSocket‘ in window){
            websocket = new WebSocket(URL);
        }else if(‘MozWebSocket‘ in window){
            websocket = new MozWebSocket(URL);
        }else{
            alert("您的浏览器不支持WebSocket,请更换最新版本浏览器");
            return;
        }

        websocket.onopen = function (evnt) {
            userName = document.getElementById(‘userId‘).value;
            if(userName == ""){
                alert("用户名不能为空");
                return;
            }else{
                setConnected(true);
                websocket.send(userName + "加入聊天室");
            }
        };
        websocket.onmessage = function (evnt) {
            onMessage(evnt)
        };
        websocket.onerror = function (evnt) {
            one rror(evnt)
        };
        websocket.onclose = function (evnt) {
            disconnect(evnt);
        }
    }
    function sendMessage() {
        var userName = document.getElementById(‘userId‘).value;
        var msg = document.getElementById(‘message‘).value;
        websocket.send(userName+": "+msg);

    }
    function onMessage(evnt) {
        if (typeof evnt.data =http://www.mamicode.com/= "string") {> 
 
 
 
 
 
 
 
 
 websocket.onopen #当打开一个新的连接时会调用这个方法 
 
 
 websocket.onmessage #当server有数据返回时调用 
 
 
 websocket.send() #向服务端发送信息，类型包括{String|ArrayBuffer|ArrayBufferView|Blob} 
 
 
 websocket.close() #向服务器发送关闭的请求，参数{number} [code]  {string} [reason]，附相关代码表，一般使用本方法关闭code为1000，直接关闭浏览器为1006，CLOSE_ABNORMAL 
 
 
 
 
 
  
 
   
 Status code 
 
   
 Name 
 
   
 Description 
 
  
 
  
 
   
 0-999 
 
   
   
 
   
 Reserved and not used. 
 
  
 
  
 
   
 1000 
 
   
 CLOSE_NORMAL 
 
   
 Normal closure; the connection successfully completed whatever purpose for which it was created. 
 
  
 
  
 
   
 1001 
 
   
 CLOSE_GOING_AWAY 
 
   
 The endpoint is going away, either because of a server failure or because the browser is navigating away from the page that opened the connection. 
 
  
 
  
 
   
 1002 
 
   
 CLOSE_PROTOCOL_ERROR 
 
   
 The endpoint is terminating the connection due to a protocol error. 
 
  
 
  
 
   
 1003 
 
   
 CLOSE_UNSUPPORTED 
 
   
 The connection is being terminated because the endpoint received data of a type it cannot accept (for example, a text-only endpoint received binary data). 
 
  
 
  
 
   
 1004 
 
   
   
 
   
 Reserved. A meaning might be defined in the future. 
 
  
 
  
 
   
 1005 
 
   
 CLOSE_NO_STATUS 
 
   
 Reserved.  Indicates that no status code was provided even though one was expected. 
 
  
 
  
 
   
 1006 
 
   
 CLOSE_ABNORMAL 
 
   
 Reserved. Used to indicate that a connection was closed abnormally (that is, with no close frame being sent) when a status code is expected. 
 
  
 
  
 
   
 1007 
 
   
   
 
   
 The endpoint is terminating the connection because a message was received that contained inconsistent data (e.g., non-UTF-8 data within a text message). 
 
  
 
  
 
   
 1008 
 
   
   
 
   
 The endpoint is terminating the connection because it received a message that violates it‘s policy. This is a generic status code, used when codes 1003 and 1009 are not suitable. 
 
  
 
  
 
   
 1009 
 
   
 CLOSE_TOO_LARGE 
 
   
 The endpoint is terminating the connection because a data frame was received that is too large. 
 
  
 
  
 
   
 1010 
 
   
   
 
   
 The client is terminating the connection because it expected the server to negotiate one or more extension, but the server didn‘t. 
 
  
 
  
 
   
 1011 
 
   
   
 
   
 The server is terminating the connection because it encountered an unexpected condition that prevented it from fulfilling the request. 
 
  
 
  
 
   
 1012-1014 
 
   
   
 
   
 Reserved for future use by the WebSocket standard. 
 
  
 
  
 
   
 1015 
 
   
   
 
   
 Reserved. Indicates that the connection was closed due to a failure to perform a TLS handshake (e.g., the server certificate can‘t be verified). 
 
  
 
  
 
   
 1016-1999 
 
   
   
 
   
 Reserved for future use by the WebSocket standard. 
 
  
 
  
 
   
 2000-2999 
 
   
   
 
   
 Reserved for use by WebSocket extensions. 
 
  
 
  
 
   
 3000-3999 
 
   
   
 
   
 Available for use by libraries and frameworks. May not be used by applications. 
 
  
 
  
 
   
 4000-4999 
 
   
   
 
   
 Available for use by applications. 
 
  
 
 
 
 

 WebSocket Java API(Server) 
 
@ServerEndpoint("/chatRoomServer")
public class MessageEndPoint {

    private static final ArrayList<Session> sessions;

    static {
        sessions = new ArrayList<Session>();
    }

    @OnOpen
    public void onOpen(Session session) {
        sessions.add(session);
    }

    @OnMessage
    public void onMessage(String message) {
        sendMessage(message);
    }

    @OnClose
    public void onClose(Session session,CloseReason closeReason) {
        sessions.remove(session);
        sendMessage(closeReason.getReasonPhrase());
    }

    private void sendMessage(String message){
        for(Session session : sessions){
            try {
                session.getBasicRemote().sendText(message);
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

}
 
  
 
 
 
 @ServerEndpoint("/chatRoomServer")，ServerEndpoint把一个POJO类转换成了WebSocket EndPoint，后边的值是访问地址 
 
 
 关于注解请看 
 
 
 
 
 
  
 
   
 Annotation 
 
   
 Role 
 
  
 
 
 
 
 
  
 
   
 
 @ServerEndpoint 
 
 
   
 
 Declare a Server Endpoint 
 
 
  
 
  
 
   
 
 @ClientEndpoint 
 
 
   
 
 Declare a Client Endpoint 
 
 
  
 
  
 
   
 
 @OnOpen 
 
 
   
 
 Declare this method handles open events 
 
 
  
 
  
 
   
 
 @OnMessage 
 
 
   
 
 Declare this method handles Websocket messages 
 
 
  
 
  
 
   
 
 @OnError 
 
 
   
 
 Declare this method handles error 
 
 
  
 
  
 
   
 
 @OnClose 
 
 
   
 
 Declare this method handles WebSocket close events 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
<dependency>
          <groupId>javax.websocket</groupId>
          <artifactId>javax.websocket-api</artifactId>
          <version>1.0</version>
          <scope>provided</scope>
      </dependency>
 我使用的tomcat，<scope>provided</scope>这句一定要加上，否则会报404，tomcat中有相关重复的类