“非法国家例外：已经连接”使用HttpURLConnection时

问题描述

当我将DoOutput设置为true时，我收到非法状态异常。

I get an illegal state exception when i set DoOutput to true.

public boolean sendLinksToMaster(String ipport, List<String> links){

        boolean sent = false;
        String[] tokens = ipport.split(":");
        String data = edu.cis555.searchengine.utils.Utils.generateLinks(links);
        HttpURLConnection conn=null;
        try{
            String encodedData = URLEncoder.encode(data, "UTF-8");
        try{

                String ip =tokens[0];
                String port = tokens[1];
                String path = edu.cis555.searchengine.utils.Constants.URL_ADD_LINK;
                System.setProperty("http.keepAlive", "false");
                URL u = new URL("http", ip, Integer.parseInt(port),"/"+path);

                conn = (HttpURLConnection)u.openConnection();
                //ERROR IN THIS LINE
                conn.setDoOutput(true);
                conn.setRequestMethod("POST");
                OutputStream stream = conn.getOutputStream();
                stream.write(encodedData.getBytes());
                stream.close();

                if(conn.getResponseCode() == HttpURLConnection.HTTP_OK)
                    sent=true;

            //  LOG.debug(conn.getResponseCode());
                conn.disconnect();
            }catch(MalformedURLException mfe){
                LOG.debug(mfe.getMessage());
                if(conn!=null){
                    conn.disconnect();
                }
            }catch(IOException ioe){
                LOG.debug(ioe.getMessage());
                if(conn!=null){
                    conn.disconnect();
                }
            }

        }catch(Exception e){
            LOG.debug(e.getMessage());
            if(conn!=null){
                conn.disconnect();
            }
        }
        return sent;

    }

显示的堆栈跟踪是：

java.lang.IllegalStateException: Already connected
at java.net.URLConnection.setDoOutput(Unknown Source)
at edu.upenn.cis455.xpathengine.utils.pool.ThreadPool.sendLinksToMaster(ThreadPool.java:357)
at edu.upenn.cis455.xpathengine.utils.pool.ThreadPool$Worker.processAndAddToQueue(ThreadPool.java:314)
at edu.upenn.cis455.xpathengine.utils.pool.ThreadPool$Worker.run(ThreadPool.java:269)
at java.lang.Thread.run(Unknown Source)

发送请求时，我没有看到任何错误。任何人都可以指出缺少什么或我做错了什么

I don't see anything I am doing wrong with sending the request. Could anyone point out what is missing or what am I doing wrong

推荐答案

我遇到了同样的问题并解决了它。就我而言，这是因为我在NetBeans的调试界面中忘记了 connection.getResponseCode（）。希望它可以帮助其他人犯同样的错误。

I got the same problem and solved it. In my case, it was caused because I had a forgotten watch for connection.getResponseCode() in my debugging interface in NetBeans. Hope it might help others making the same mistake.

如果你有相对于请求响应值的任何监视，例如 getResponseCode（） ， getResponseMessage（）， getInputStream（）甚至只是 connect（），你会在调试模式下得到这个错误。

If you have any watch relative to the response value of the request, such as getResponseCode(), getResponseMessage(), getInputStream() or even just connect(), you will get this error in debugging mode.

所有以前的方法都隐式调用 connect（ ）并触发请求。因此，当您到达 setDoOutput 时，已建立连接。

All of the previous methods implicitly call connect() and fire the request. So when you reach setDoOutput, the connection is already made.

这篇关于“非法国家例外：已经连接”使用HttpURLConnection时的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！