(Java) HTTP POST and Stream Response to File

Demonstrates how to send an HTTP POST and stream the response body directly to a file.

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import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkRest rest = new CkRest();

    CkUrl url = new CkUrl();
    // This URL will emit a response that echos the query params (name and age)
    url.ParseUrl("https://www.chilkatsoft.com/readPost.asp");

    // Connect to the web server
    boolean bAutoReconnect = true;
    boolean success = rest.Connect(url.host(),url.get_Port(),url.get_Ssl(),bAutoReconnect);
    if (success != true) {
        System.out.println(rest.lastErrorText());
        return;
        }

    rest.AddQueryParam("name","John");
    rest.AddQueryParam("age","33");

    //  Send the HTTP POST.
    success = rest.SendReqFormUrlEncoded("POST",url.path());
    if (success != true) {
        System.out.println(rest.lastErrorText());
        return;
        }

    // Read the response header.
    int responseStatusCode = rest.ReadResponseHeader();
    if (responseStatusCode < 0) {
        System.out.println(rest.lastErrorText());
        return;
        }

    System.out.println("Response status code = " + responseStatusCode);

    // We expect a 200 response status if the file data is coming.
    // Otherwise, we'll get a string response body with an error message(or no response body).
    if (responseStatusCode == 200) {

        CkStream bodyStream = new CkStream();

        // The stream's sink will be a file.
        bodyStream.put_SinkFile("qa_output/out.txt");

        // Read the response body to the stream.  Given that we've
        // set the stream's sink to a file, it will stream directly
        // to the file.
        success = rest.ReadRespBodyStream(bodyStream,true);
        if (success != true) {
            System.out.println(rest.lastErrorText());
            return;
            }

        System.out.println("Successfully streamed the response to a file.");

        }
    else {
        String errResponse = rest.readRespBodyString();
        if (rest.get_LastMethodSuccess() != true) {
            System.out.println(rest.lastErrorText());
            }
        else {
            System.out.println(errResponse);
            }

        }
  }
}