Using Keytool in a java program?

Question

I am trying to write a program to generate RSA keys private.der, and public.der in PKCS#8, DER format.

I can do it in OpenSSL manually easily, but I have no idea how to do it in java. I read about Keytool that you can also use manually. But I want to automate the process in a program to generate a unique usable keypair each time the program is ran, and export them to a folder.

Any help would be appreciated.

Answer 1

Key generation works as follows:

KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");
keyGen.initialize(2048); // Keysize
KeyPair kp = keyGen.genKeyPair():
PrivateKey privKey = kp.getPrivate();
PublicKey pubKey = kp.getPublic();

Then use privKey.getEncoded() and pubKey.getEncoded() to get the encoded versions.