(Java) HTTP multipart/form-data Upload

Demonstrates how to upload files to an HTTP server using a multipart/form-data POST.

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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.

    CkHttp http = new CkHttp();

    CkHttpRequest req = new CkHttpRequest();
    req.put_HttpVerb("POST");
    req.put_ContentType("multipart/form-data");
    req.put_Path("rcvFormDataUpload.aspx");

    // Send an "Expect: 100-continue" header in the request.
    // This causes the HTTP server to end a 100-continue response
    // immediately after receiving the HTTP header.  The client
    // (Chilkat) will receive this intermediate response, and if
    // it's not an error response, it knows that the HTTP server will
    // accept the data that is forthcoming.
    // The alternative is to get an error response after trying to upload
    // the entire contents of the files.
    req.AddHeader("Expect","100-continue");

    // Call AddFileForUpload2 for each file to be uploaded in the HTTP multipart/form-data POST
    // To allow Chilkat to determine the content-type automatically based on file-extension,
    // call AddFileForUpload instead.

    // The 1st arg is the filename passed in the HTTP request.
    // The 2nd arg is the path in the local filesytem.
    // The file is not loaded into memory.  It is streamed directly from the file
    // when the HTTP POST is sent.
    boolean success = req.AddFileForUpload2("starfish.jpg","c:/qa_data/starfish.jpg","image/jpg");
    if (success != true) {
        System.out.println(req.lastErrorText());
        return;
        }

    success = req.AddFileForUpload("something.pdf","c:/qa_data/something.pdf");
    if (success != true) {
        System.out.println(req.lastErrorText());
        return;
        }

    // Its also possible to add a file from a string:
    success = req.AddStringForUpload("test.xml","test.xml","<abc>This is the test.xml content</abc>","utf-8");
    // We'll assume success since no files are involved..

    // This sends the HTTP request (with 3 files being uploaded) to
    // http://www.mywebserver123abc.com/rcvFormDataUpload.aspx
    CkHttpResponse resp;
    resp = http.SynchronousRequest("www.mywebserver123abc.com",80,false,req);
    if (http.get_LastMethodSuccess() != true) {
        System.out.println(http.lastErrorText());
        }
    else {
        System.out.println("HTTP response status: " + resp.get_StatusCode());
        // See the online reference documentation for 
        // other information that can be obtained from the response object.

        }

    // To send using SSL/TLS, do this instead.
    // This sends to https://www.mywebserver123abc.com/rcvFormDataUpload.aspx
    resp = http.SynchronousRequest("www.mywebserver123abc.com",443,true,req);
    if (http.get_LastMethodSuccess() != true) {
        System.out.println(http.lastErrorText());
        }
    else {
        System.out.println("HTTP response status: " + resp.get_StatusCode());
        // See the online reference documentation for 
        // other information that can be obtained from the response object.

        }
  }
}