SSE服务器推送事件

2018-05-28

1. 新建一个演示控制器，代码如下

/**
 * 
 */
package com.zhazhapan.spring.springtest;
import java.util.Random;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
/**
 * @author pantao
 *
 */
@Controller
public class SseController {
	@RequestMapping(value = "/push", produces = "text/event-stream")
	public @ResponseBody String push() {
		Random random = new Random();
		try {
			Thread.sleep(5000);
		} catch (InterruptedException e) {
			e.printStackTrace();
		}
		return "data:Testing " + random.nextInt() + "\n\n";
	}
}

2. 添加jquery.js到src/main/resources/assets/js目录下（没有的话可以新建），下载jQuery-3.2.1

3. 在src/main/resources/views目录下新建演示页面sse.jsp，内容如下

<%@ page language="java" contentType="text/html; charset=UTF-8"
	pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>SSE Demo</title>
</head>
<body>
	<div id="msgFromPush"></div>
	<script type="text/javascript" src="assets/js/jquery-3.2.1.js"></script>
	<script type="text/javascript" type="text/javascript">
		//只有新式的浏览器才有，EventSource是SSE的客户端
		if (!!window.EventSource) {
			var source = new EventSource('push');
			s = '';
			//添加SSE监听，获得服务器推送的消息
			source.addEventListener('message', function(e) {
				s += e.data + "<br/>";
				$('#msgFromPush').html(s);
			});
			source.addEventListener('open', function(e) {
				console.log("连接打开");
			});
			source.addEventListener('error', function(e) {
				if (e.readyState == EventSource.CLOSED) {
					console.log('连接关闭');
				} else {
					console.log(e.readyState);
				}
			})
		} else {
			console.log('你的浏览器不支持SSE');
		}
	</script>
</body>
</html>

4. 添加路径映射

//这是一个继承自WebMvcConfigurerAdapter的配置类
@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
	//对外暴露访问路径
	registry.addResourceHandler("/assets/**").addResourceLocations("classpath:/assets/");
}
@Override
public void addViewControllers(ViewControllerRegistry registry) {
	registry.addViewController("/sse").setViewName("/sse");
}

5. 运行效果

图片：运行效果