(Java) Streaming Decrypt HTTP Response

If the an encrypted file was previously uploaded, this example demonstrates how to download and decrypt in a streaming way.

Chilkat Java Downloads Java Libs for Windows, MacOS, Linux, Alpine Linux, Solaris Java Libs for Android

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();

    boolean bTls = true;
    int port = 443;
    boolean bAutoReconnect = true;
    boolean success = rest.Connect("chilkatdownload.com",port,bTls,bAutoReconnect);

    // Send the request to download a file.
    success = rest.SendReqNoBody("GET","/9.5.0.83/chilkat-9.5.0-python-3.8-x64.zip");
    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 JPG data is coming.
    // Otherwise, we'll get a string response body with an error message(or no response body).
    if (responseStatusCode != 200) {
        String errResponse = rest.readRespBodyString();
        if (rest.get_LastMethodSuccess() != true) {
            System.out.println(rest.lastErrorText());
            }
        else {
            System.out.println(errResponse);
            }

        return;
        }

    // Create an object for decrypting.
    // This example will use "none" for the encryption algorithm, which means it's just a pass-through.
    // Typically you would set the decrypt properties, such as secret key, IV, key length, padding scheme, cipher mode..
    CkCrypt2 crypt = new CkCrypt2();
    crypt.put_CryptAlgorithm("none");

    // The following settings are ignored in this test because our CryptAlgorithm is "none".
    // However, if you were truly decrypting, you might set CryptAlgorithm = "aes".
    crypt.put_CipherMode("cbc");
    crypt.put_KeyLength(128);
    crypt.SetEncodedKey("000102030405060708090A0B0C0D0E0F","hex");
    crypt.SetEncodedIV("000102030405060708090A0B0C0D0E0F","hex");

    CkStream receiveStream = new CkStream();
    // The decryptStream's source will be the receiveStream.
    CkStream decryptStream = new CkStream();

    // The decrypt stream's sink will be a file.
    decryptStream.put_SinkFile("qa_output/chilkat-9.5.0-python-3.8-x64.zip");
    decryptStream.SetSourceStream(receiveStream);

    // Create and run a background async task to decrypt incoming data and write to a file.
    CkTask decryptStreamTask = crypt.DecryptStreamAsync(decryptStream);
    success = decryptStreamTask.Run();

    success = rest.ReadRespBodyStream(receiveStream,true);
    if (success != true) {
        System.out.println(rest.lastErrorText());
        return;
        }

    System.out.println("Successfully received the .zip file.");
  }
}