(Java) RSA Encrypt with Modulus and Exponent

Demonstrates how to RSA encrypt with a given modulus and exponent.

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();

    // Assuming you already have a base64 modulus and exponent,
    // wrap it in XML like this:
    String modulus = "qMBRpdYrAy5aMmo31NErUizh5sbweguSmh4wlK6uJEIDl+kwTlROnE34KOFExeTbJSX0WygPi+vWl0yNq7buIMUKpytossAAWut5khO3CQJxTk7G2gnEPNUUXHiExGgNrLzcSLv8YIlfVALhoRWyC67KOL+a+3taNq3h+BHeWhM=";
    String exponent = "AQAB";

    CkXml xml = new CkXml();
    xml.put_Tag("RSAPublicKey");
    xml.NewChild2("Modulus",modulus);
    xml.NewChild2("Exponent",exponent);

    CkPublicKey pubKey = new CkPublicKey();
    success = pubKey.LoadFromString(xml);
    if (success == false) {
        System.out.println(pubKey.lastErrorText());
        return;
        }

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

    boolean usePrivateKey = false;
    String plainText = "message in a bottle";

    rsa.put_EncodingMode("base64");
    String encryptedStrBase64 = rsa.encryptStringENC(plainText,usePrivateKey);
    System.out.println(encryptedStrBase64);
  }
}