我怎样才能防止**”；java.net.ProtocolException:读取输入后无法写入输出“**”Java中的错误代码？

我试图将数据发送到url，但显示错误：

java.net.ProtocolException:读取输入后无法写入输出

我认为发生错误是因为行

int responseCode=connection.getResponseCode（）我不知道
知道如何解决这个问题

    URL Transmeter_Url = new URL(data);
    HttpURLConnection connection = (HttpURLConnection) Transmeter_Url.openConnection();
    connection.setRequestMethod("POST");
    connection.setDoOutput(true);
    connection.setDoInput(true);
    connection.setUseCaches(false);

    connection.setRequestProperty("Content-Type",Contetn_Type);
    connection.setRequestProperty("Contetn-Length", Integer.toString(Post_Value.length()));
    connection.setRequestProperty("User-Agent", "Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.4; en- 
    US; rv:1.9.2.2) Gecko/20100316 Firefox/3.6.2");

    int responseCode = connection.getResponseCode();
    System.out.println("Get Response code:"+responseCode);

    System.out.println("Reached here 7");

    OutputStream outputStream = connection.getOutputStream();

    System.out.println("Reached here 7");

    outputStream.write(Post_Value.getBytes());
    outputStream.flush();
    outputStream.close();