EventSource 对象用于接收服务器发送事件通知,是网页自动获取来自服务器的更新

//--------------------------------客户端代码-----------------------------

if(typeof(EventSource) !== "undefined") {
var source = new EventSource("../api/v1/event.source");
source.onmessage = function(event) {
$("#content_event").html(event.data + "<br>");
};
}
else {
$("#content_event").html("你的浏览器不支持 server-sent事件");
}

//--------------------------------服务端代码-----------------------------
@RequestMapping(value = "/event.source",method = {RequestMethod.POST,RequestMethod.GET})
@ResponseBody
public String eventSource(HttpServletResponse response) throws Exception
{
   try
     {
response.setHeader("Content-Type", "text/event-stream");//必须
response.setHeader("Cache-Control", "no-cache");
      response.setCharacterEncoding("UTF-8");
      response.setHeader("Pragma","no-cache");
      response.setDateHeader("Expires",0);
      String serverDateTime = "data:"+CommanUtil.getCurrentDatetime()+" ";//必须以data:开头；以结尾
      return serverDateTime;
  }
  catch(Exception e)
  {
      logger.debug(e.getMessage().toString());
      return e.getMessage().toString();
  }

}

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如果数据比较长时，可以采用多行data：然后js客户端使用event.data.split(' ').join('')组合数据