(Java) PKCS7 Sign Text using RSA 2048, SHA256, Base64 Output

Demonstrates how to sign text using 2048-bit RSA with SHA256, producing PKCS#7 output in Base64. The certificate w/ private key used for signing is loaded from a .p12/.pfx 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.

    CkCert cert = new CkCert();

    // Load the cert and private key.  Whatever the private key happens to be,
    // such as RSA or ECC, then Chilkat will use it.  If the private key is 
    // a 2048-bit RSA key, then that's what will be used..
    boolean success = cert.LoadPfxFile("qa_data/pfx/myCertAndKey.p12","password");
    if (success != true) {
        System.out.println(cert.lastErrorText());
        return;
        }

    CkCrypt2 crypt = new CkCrypt2();

    success = crypt.SetSigningCert(cert);
    if (success != true) {
        System.out.println(crypt.lastErrorText());
        return;
        }

    // Use SHA-256
    crypt.put_HashAlgorithm("sha256");

    // Hash the utf-8 byte representation of the string
    crypt.put_Charset("utf-8");

    // Return the result in base64
    crypt.put_EncodingMode("base64");

    // Sign some text..
    String textToSign = "This is the text to be hashed and signed.";
    String sigBase64 = crypt.opaqueSignStringENC(textToSign);
    if (crypt.get_LastMethodSuccess() != true) {
        System.out.println(crypt.lastErrorText());
        return;
        }

    System.out.println(sigBase64);

    // The result:
    // MIIS2wYJKoZIhvcNAQc ... zGeeY4Oxg==
  }
}