线程“main”中的异常 java.lang.IllegalStateException：已连接

Question

我正在尝试调用网络服务调用并获得响应。 当我第一次尝试它时，它运行良好并打印了响应。 但在那一跑之后，我跑了多少次，我把我扔了

Exception in thread "main" java.lang.IllegalStateException: Already connected
    at sun.net.www.protocol.http.HttpURLConnection.setRequestProperty(Unknown Source)
    at SOAPClient4XG.main(SOAPClient4XG.java:72)

我尝试了为类似问题提供的各种解决方案（如连接/断开连接），但似乎没有任何效果。 我知道它尝试对现有连接执行操作，但不确定如何修复。 我对这一切都很陌生，我需要帮助。

下面是我的代码

    import java.io.*;
    import java.net.*;

    public class SOAPClient4XG 
    {
     private static HttpURLConnection httpConn;
     public static void main(String[] args) throws Exception {

     String SOAPUrl      = args[0];
     String xmlFile2Send = args[1];*/

     String SOAPUrl      = "http://10.153.219.88:8011/celg-svcs-soap/business/ApplicantEligibility";
     String xmlFile2Send = 
    "C:\\Users\\dkrishnamoorthy\\workspace\\SOAPUI_Automation\\src\\ApplicantElligibilty.xml";

          String SOAPAction = "";
        if (args.length  > 2) 
                SOAPAction = args[2];

        // Create the connection where we're going to send the file.
        URL url = new URL(SOAPUrl);
        URLConnection connection = url.openConnection();
        //URLConnection connection = new URLConnection(url);

        httpConn = (HttpURLConnection) connection;

        if(httpConn.getResponseCode()==500)
        {
            System.out.println("Error Stream for 500 : "+httpConn.getErrorStream());
        }

        // Open the input file. After we copy it to a byte array, we can see
        // how big it is so that we can set the HTTP Cotent-Length
        // property. (See complete e-mail below for more on this.)

        FileInputStream fin = new FileInputStream(xmlFile2Send);

        ByteArrayOutputStream bout = new ByteArrayOutputStream();

        // Copy the SOAP file to the open connection.
        copy(fin,bout);
        fin.close();

        byte[] b = bout.toByteArray();

        // Set the appropriate HTTP parameters.
        httpConn.setRequestProperty( "Content-Length",
                                     String.valueOf( b.length ) );
        httpConn.setRequestProperty("Content-Type","text/xml; charset=utf-8");
          httpConn.setRequestProperty("SOAPAction",SOAPAction);
        httpConn.setRequestMethod( "POST" );
        httpConn.setDoOutput(true);
        httpConn.setDoInput(true);

      //  httpConn.connect();

        // Everything's set up; send the XML that was read in to b.
        OutputStream out = httpConn.getOutputStream();
        out.write( b );    
        out.close();

        // Read the response and write it to standard out.

        InputStreamReader isr =
            new InputStreamReader(httpConn.getInputStream());
        BufferedReader in = new BufferedReader(isr);

        String inputLine;
        System.out.println("Printing the Response ");

        while ((inputLine = in.readLine()) != null)
            System.out.println(inputLine);

        in.close();
    }

  public static void copy(InputStream in, OutputStream out) 
   throws IOException {


    synchronized (in) {
      synchronized (out) {

        byte[] buffer = new byte[256];
        while (true) {
          int bytesRead = in.read(buffer);
          if (bytesRead == -1) break;
          out.write(buffer, 0, bytesRead);
        }
      }
    }
  } 
}

Answer 1

您可以延迟调用urlConnection.getResponseCode（）吗？ 那就是你的问题所在。 在该调用之前设置请求标头和请求方法应该可以解决该问题。

Answer 2

如果您使用 eclipse 版本，只需重新启动它。 我遇到了同样的问题，我通过这样做来解决。

Answer 3

我解决了这个问题，因为我在 NetBeans 的调试界面中忘记了 connection.getResponseCode() 的监视。 希望它可以帮助其他犯同样错误的人。

如果您有任何与请求的响应值相关的监视，例如 getResponseCode()、getResponseMessage()、getInputStream() 甚至只是 connect()，您将在调试模式下收到此错误。

前面的所有方法都隐式调用 connect() 并触发请求。 所以当你到达 setDoOutput 时，连接已经建立。