(Java) Generate an RSA Key and Get as Base64 DER

Demonstrates how to generate a 2048-bit RSA key and return the public and private parts as unencrypted Base64 encoded DER.

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

    CkRsa rsa = new CkRsa();

    // Generate a 2048-bit key.
    CkPrivateKey privKey = new CkPrivateKey();
    success = rsa.GenKey(2048,privKey);
    if (success == false) {
        System.out.println(rsa.lastErrorText());
        return;
        }

    // Get the public part of the key.
    CkPublicKey pubKey = new CkPublicKey();
    privKey.ToPublicKey(pubKey);

    // There are two possible formats for representing the RSA public key 
    // in ASN.1 (DER).  The possible formats are PKCS1 and PKCS8.
    // We can get either by setting bChoosePkcs1 to true or false.
    boolean bChoosePkcs1 = true;
    String pubKeyBase64Der = pubKey.getEncoded(bChoosePkcs1,"base64");
    System.out.println("Public Key Base64 DER:");
    System.out.println(pubKeyBase64Der);

    // Get the private key as Base64 DER:
    // We can get PKCS1 or PKCS8, but with different methods:
    String privKeyPkcs1 = privKey.getPkcs1ENC("base64");
    System.out.println("Private Key PKCS1 Base64 DER:");
    System.out.println(privKeyPkcs1);

    String privKeyPkcs8 = privKey.getPkcs8ENC("base64");
    System.out.println("Private Key PKCS8 Base64 DER:");
    System.out.println(privKeyPkcs8);
  }
}