网上搜了好多都是用 SseEmitter 实现的,自己搭的demo确实也可以了,但是我项目里有一个过滤器,死活配置都不行,终于用google搜了一下,第一篇帖子便解决了这个问题,代码和大佬链接如下:

https://github.com/CodingChaozhang/spring_boot_practice_demo/blob/master/springboot_sse/Spring%20boot%E6%95%B4%E5%90%88SSE%E5%AE%9E%E7%8E%B0%E6%9C%8D%E5%8A%A1%E5%99%A8%E5%AE%9E%E6%97%B6%E6%8E%A8%E9%80%81%E6%B5%81%E4%BF%A1%E6%81%AF.md

@GetMapping(value = "/getTrue")
    public void getData_True(HttpServletResponse response) {
        response.setContentType("text/event-stream");
        response.setCharacterEncoding("utf-8");

        System.out.println("准备发消息");
        try {
            PrintWriter pw = response.getWriter();
            for (int i = 0; i < 5; i++) {
                if (pw.checkError()) {
                    System.out.println("客户端断开连接");
                    break;
                }
                Thread.sleep(1000);
                String ss = "data:实时返回的随机数:" + Math.random() + "\n\n";
                System.out.println(i + "   " + ss);
                pw.write(ss);
                pw.flush();
            }
            pw.close();
        } catch (IOException | InterruptedException e) {
            e.printStackTrace();
        }
        System.out.println("发消息完毕");
    }