Sign a JWS with a Private Key

See more JSON Web Signatures (JWS) Examples

Demonstrates Jws.SetPrivateKey, which sets the private key used to create a signature. The example uses RS256 (RSASSA-PKCS1-v1_5 with SHA-256).

The file path is relative to the application's current working directory. An absolute path may also be used. Supply the path appropriate to your own environment.

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[])
  {
    boolean success = false;

    CkJws jws = new CkJws();

    //  Protected header specifying RSASSA-PKCS1-v1_5 with SHA-256 (RS256).
    CkJsonObject header = new CkJsonObject();
    header.UpdateString("alg","RS256");
    success = jws.SetProtectedHeader(0,header);
    if (success == false) {
        System.out.println(jws.lastErrorText());
        return;
        }

    boolean bIncludeBom = false;
    success = jws.SetPayload("This is the content to sign.","utf-8",bIncludeBom);
    if (success == false) {
        System.out.println(jws.lastErrorText());
        return;
        }

    //  The file path is relative to the application's current working directory.  An absolute path
    //  may also be used.  Supply the path appropriate to your own environment.
    //  Load the signer's private key and set it for signature 0.
    CkPrivateKey privKey = new CkPrivateKey();
    success = privKey.LoadPemFile("qa_data/signer_privkey.pem");
    if (success == false) {
        System.out.println(privKey.lastErrorText());
        return;
        }

    success = jws.SetPrivateKey(0,privKey);
    if (success == false) {
        System.out.println(jws.lastErrorText());
        return;
        }

    String jwsCompact = jws.createJws();
    if (jws.get_LastMethodSuccess() == false) {
        System.out.println(jws.lastErrorText());
        return;
        }

    System.out.println(jwsCompact);
  }
}