(Java) RSA Sign using Base64 Private Key

Signs a string using a non-encrypted RSA private key in base64 encoding. Returns the RSA signature as a base64 string.

Note: This example requires Chilkat v11.0.0 or greater.

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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[])
  {
    boolean success = false;

    // This requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkPrivateKey privKey = new CkPrivateKey();

    CkStringBuilder sbPem = new CkStringBuilder();
    sbPem.AppendLine("-----BEGIN RSA PRIVATE KEY-----",true);
    sbPem.AppendLine("MIIC .... j5A==",true);
    sbPem.AppendLine("-----END RSA PRIVATE KEY-----",true);

    success = privKey.LoadPem(sbPem.getAsString());
    if (success == false) {
        System.out.println(privKey.lastErrorText());
        return;
        }

    CkRsa rsa = new CkRsa();

    success = rsa.UsePrivateKey(privKey);
    if (success == false) {
        System.out.println(rsa.lastErrorText());
        return;
        }

    CkBinData bd = new CkBinData();
    bd.AppendString("12345678","utf-8");

    success = rsa.SignRawBd(bd);
    if (success == false) {
        System.out.println(rsa.lastErrorText());
        return;
        }

    // Get the base64 RSA signature.
    System.out.println(bd.getEncoded("base64"));

    success = rsa.VerifyRawBd(bd);
    if (success == false) {
        System.out.println(rsa.lastErrorText());
        return;
        }

    String strOriginal = bd.getString("utf-8");
    System.out.println(strOriginal);
  }
}