springmvc不斷輸出文本到網頁

背景

有一些批處理的東東，後臺執行可能超時，若是等最後遇到錯誤或者有什麼結果才返回，每每會超時，並且整個執行過程的細節也都無法看到，是個黑盒，不大方面調試。這裏講一下若是實現相似websocket的效果，就是後端不斷往流裏頭寫文本。

controller

@Controller
@RequestMapping("/echo")
public class EchoController {

    @RequestMapping(value = "/reply",method = RequestMethod.GET)
    public void writeStream(HttpServletResponse response) throws IOException, InterruptedException {
        response.setContentType("text/html;charset=utf-8");
        for(int i=0;i<1000;i++){
            write(response,"hello");
            Thread.sleep(1000*2);
            System.out.println("send");
        }

        response.getWriter().close();
    }

    private void write(HttpServletResponse response,String content) throws IOException {
        response.getWriter().write(content+"<br/>");
        response.flushBuffer();
        response.getWriter().flush();
    }
}

運行

➜  ~ wget http://localhost:8080/echo/reply
--2017-06-14 16:08:14--  http://localhost:8080/echo/reply
Resolving localhost... ::1, 127.0.0.1
Connecting to localhost|::1|:8080... connected.
HTTP request sent, awaiting response... 200
Length: unspecified [text/html]
Saving to: 'reply'

reply                   [     <=>            ]      60  5.99 B/s

而後tail一下

➜  ~ tail -f reply
hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>hello<br/>

或者用瀏覽器訪問就能夠看到效果了.

直接curl貌似看不到效果

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