教程
一:jar包
maven配置
<
dependency
>
<
groupId
>javax.websocket
</
groupId
>
<
artifactId
>javax.websocket-api
</
artifactId
>
<
version
>1.1
</
version
>
<
scope
>provided
</
scope
>
</
dependency
>
<
dependency
>
<
groupId
>org.springframework
</
groupId
>
<
artifactId
>spring-websocket
</
artifactId
>
<
version
>4.1.6.RELEASE
</
version
>
</
dependency
>
注意:spring-websocket的包版本要与spring的包版本保持一致,不然可能在项目启动的时候回报错;
一:.WebSocketConfig.java (websocket核心配置文件,可以配置websocket的映射路径,监听等功能)
内容代码如下
:
@Configuration
@ComponentScan
(basePackages
= {
"com.config.websocket"
}
)
@EnableWebSocket
public class
WebSocketConfig
extends
WebMvcConfigurerAdapter
implements
WebSocketConfigurer
{
@Resource
MyWebSocketHandler
handler
;
public void
registerWebSocketHandlers
(
WebSocketHandlerRegistry registry
)
{
registry
.addHandler
(
handler
,
"/ws.json"
)
.addInterceptors
(
new HandShake
())
.setAllowedOrigins
(
"*"
)
;
registry
.addHandler
(
handler
,
"/ws/sockjs"
)
.addInterceptors
(
new HandShake
())
.withSockJS
()
;
}
}
@Configuration 指明该类为Spring 配置类
@EnableWebSocket 声明该类支持WebSocket
红色方框表示 handler(消息处理对象)位置;
红色横线表示将ws:hostPath/ws.json的请求映射到handle消息处理类中;
注意:配置路径时候注意项目springMvc的捕获请求的路径,不然在项目中会找不到请求,我的项目中springmvc后缀为json所以是/ws.json;
荧光绿波浪线表示注册自定义的拦截器的位置;拦截器是SpringWebsocket提供的功能,并非websocket所必须的配置,可自行根据业务进行选择是否配置;
黄色横线
setAllowedOrigins方法用来设置来自那些域名的请求可访问,默认为localhost ,不设置的话socket链接的时候会被拒绝:提示
Unexpected response code: 403;(深坑)
二:
MyWebSocketHandler.java(消息处理类,实现
WebSocketHandler接口,里面有socket声明周期的所有方法
)
对应链接,建立,前台发送消息,链接关闭等方法 都是相应api 没有什么很奇怪的点;后台向浏览器推送消息,就使用WebSocketSession的sendMessage方法
三:自定义的拦截器;
public class
HandShake
implements
HandshakeInterceptor
{
public boolean
beforeHandshake
(
ServerHttpRequest request
,
ServerHttpResponse response
,
WebSocketHandler wsHandler
,
Map
<
String
,
Object
> attributes
)
throws
Exception
{
// System.out.println("Websocket:用户[ID:" + ((ServletServerHttpRequest) request).getServletRequest().getSession(false).getAttribute("uid") + "]已经建立连接");
// if (request instanceof ServletServerHttpRequest) {
// ServletServerHttpRequest servletRequest = (ServletServerHttpRequest) request;
// HttpSession session = servletRequest.getServletRequest().getSession(false);
// // 标记用户
// Long uid = (Long) session.getAttribute("uid");
// if(uid!=null){
// attributes.put("uid", uid);
// }else{
// return false;
// }
// }
System
.
out
.println
(
"拦截器拦截到ws请求"
)
;
return true
;
}
public void
afterHandshake
(
ServerHttpRequest request
,
ServerHttpResponse response
,
WebSocketHandler wsHandler
,
Exception exception
)
{
}
}
实现HandshakeInterceptor接口,实现
beforeHandshake方法,true表示放行请求,可以进行权限或者公共信息处理;
前台调用的代码
var websocket;
if ('WebSocket' in window) {
websocket = new WebSocket("ws://" + path + "/ws?uid="+uid);
} else if ('MozWebSocket' in window) {
websocket = new MozWebSocket("ws://" + path + "/ws"+uid);
} else {
websocket = new SockJS("http://" + path + "/ws/sockjs"+uid);
}
websocket.onopen = function(event) {
console.log("WebSocket:已连接");
console.log(event);
};
websocket.onmessage = function(event) {
var data=JSON.parse(event.data);
console.log("WebSocket:收到一条消息",data);
};
websocket.onerror = function(event) {
console.log("WebSocket:发生错误 ");
console.log(event);
};
websocket.onclose = function(event) {
console.log("WebSocket:已关闭");
console.log(event);
}