服務端：
Controller：
package com.example.demo;
import java.io.IOException;
import javax.annotation.Resource;
import javax.servlet.http.HttpServletResponse;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.context.request.async.DeferredResult;
import com.example.demo.service.MsgService;
@Controller
@RequestMapping("/")
public class MsgControl {
@Resource(name="msgService")
private MsgService msgService;
@ResponseBody
@RequestMapping(value = "/getMsg", produces="text/event-stream;charset=UTF-8")
DeferredResult<String> getMsg(HttpServletResponse response) throws IOException {
response.setContentType("text/event-stream");
response.setCharacterEncoding("UTF-8");
response.setStatus(200);
msgService.removeErrorResponse();
msgService.getListRes().add(response);
if(!response.getWriter().checkError()){
response.getWriter().write("data:hello\n\n");
response.getWriter().flush();
}
DeferredResult<String> df = new DeferredResult<String>(60000l);
return df;
}
}
Service：
package com.example.demo.service;
import java.io.PrintWriter;
import java.util.Iterator;
import java.util.Vector;
import java.util.Random;
import javax.servlet.http.HttpServletResponse;
import org.springframework.context.annotation.Lazy;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Service;
@Lazy(value = false)
@EnableScheduling
@Service(value="msgService")
public class MsgService {
final Vector<HttpServletResponse> list_res= new Vector<HttpServletResponse>();
public Vector<HttpServletResponse> getListRes()
{
return list_res;
}
@Scheduled(initialDelay = 0, fixedDelay = 3*1000)
public void run() {
this.removeErrorResponse();
Iterator<HttpServletResponse> it = list_res.iterator();
Random rand =new Random();
int num=rand.nextInt(100);
while(it.hasNext())
{
PrintWriter pw = null;
try {
pw = it.next().getWriter();
if(pw == null || pw.checkError())
{
continue;
}
pw.write("data:msg: hello, the random num is: " + num + "\n\n");
pw.flush();
} catch (Exception e) {
}
}
}
public synchronized void removeErrorResponse(){
Iterator<HttpServletResponse> it = list_res.iterator();
while(it.hasNext())
{
PrintWriter pw = null;
try {
pw = it.next().getWriter();
if(pw == null)
{
it.remove();
continue;
}
else if(pw.checkError()){
pw.close();
it.remove();
continue;
}
} catch (Exception e) {
it.remove();
}
}
}
}
前端代碼：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>信息</title>
</head>
<body>
<div id='msg'>
</div>
<script>
if (typeof(EventSource) !== "undefined") {
var eventSource = new EventSource("/getMsg");
eventSource.onmessage = function (event) {
document.getElementById("msg").innerHTML = event.data;
}
eventSource.addEventListener('error', function (event) {
console.log("錯誤：" + event);
});
eventSource.addEventListener('open', function (event) {
console.log("建立連接：" + event);
});
}
else {
document.getElementById("msg").innerHTML = "抱歉，您的瀏覽器不支持 server-sent 事件 ...";
}
</script>
</body>
</html>
運行結果：
