(Java) Generate a Random 256-bit AES Key and RSA Encrypt

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Generates a random 256-bit AES key and encrypts using an RSA public key. Only the owner of the RSA private key will be able to decrypt the AES key.

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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[])
  {
    // The RSA public key is used for encryption, and the private key for decryption.

    // The public key's role is to make encryption accessible to anyone while ensuring that
    // only the private key holder can decrypt the messages.
    // The public key is designed to be widely distributed so anyone can use it to encrypt messages
    // intended for the owner of the private key.

    // Load our 2048-bit RSA public key.
    CkPublicKey pubKey = new CkPublicKey();
    // In all Chilkat methods expecting a path, you pass either absolute or relative paths.
    boolean success = pubKey.LoadFromFile("rsaKeys/Test2048Rsa.pem");
    if (success == false) {
        System.out.println(pubKey.lastErrorText());
        return;
        }

    CkRsa rsa = new CkRsa();

    // Tell RSA to use the public key.
    rsa.ImportPublicKeyObj(pubKey);

    // Generate a random 256-bit AES key (32 bytes)
    CkBinData bdAesKey = new CkBinData();
    CkPrng prng = new CkPrng();
    prng.GenRandomBd(32,bdAesKey);

    // RSA encrypt.
    rsa.EncryptBd(bdAesKey,false);

    // Save the RSA encrypted AES key to a file.
    success = bdAesKey.WriteFile("rsaEncrypted/myAes.key");
  }
}