HttpURLConnection: java.lang.IllegalStateException: Already connected

Question

I\'m trying to use HttpURLClient to send some POST data to a server using the HttpRestClient class shown below. When executing

conn.setDoInput(true)         


        

Answer 1

You called both of conn.setDoInput(true); and conn.setDoOutput(true);. Use one of them:

• setDoOutput(true) is used for POST and PUT requests.
• setDoInput(true) is used for GET request.

The connection you made was confused, it can't decide which request should be used.

In your code:

static public int post(String urlStr, List data){
    HttpURLConnection conn = null;
    System.setProperty("http.keepAlive", "false"); // must be set
    try {
        ...
        conn.setDoOutput(true);
        conn.setRequestMethod("POST");
        // and connect to server, if needed
        conn.connect();
        ...
    }
....