Question

If the temp string is very large I get java.io.IOException: Error writing to server at getInputStream

String tmp  = js.deepSerialize(taskEx);
URL url = new URL("http://"
                    + "localhost"
                    + ":"
                    + "8080"
                    + "/Myproject/TestServletUpdated?command=startTask&taskeId=" +taskId + "'&jsonInput={\"result\":"
                    + URLEncoder.encode(tmp) + "}"); 

                    URLConnection conn = url.openConnection();
                     InputStream is = conn.getInputStream();

Why is that?
This call goes to the servlet mentioned in the URL.

Answer 1

I think you might have a “too long url”, the maximum number of characters are 2000 (see this SO post for more info). GET requests are not made to handle such long data input.

You can, if you can change the servlet code also, change it into a POST instead of a GET request (as you have today). The client code would look pretty simular:

public static void main(String[] args) throws IOException {

    URL url = new URL("http", "localhost:8080", "/Myproject/TestServletUpdated");

    URLConnection conn = url.openConnection();
    conn.setDoOutput(true);

    OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
    wr.write("command=startTask" +
             "&taskeId=" +taskId +
             "&jsonInput={\"result\":" + URLEncoder.encode(tmp) + "}");
    wr.flush();


    .... handle the answer ...
}

---

I didn’t see it first but it seems like you have a single quote character in your request string.

...sk&taskeId=" + taskId + "'&jso.....
                            ^

try removing it, it might help you!