I've researched a bit about how to achieve what I said in the question and found several APIs but most of them look very complicated and since I'm just a noobie in this area I just want a simple method like:

```
public String Encrypt(String message, PublicKey publicKey)

```

Don't know if this can be done? If not then please someone enlighten me another way to achieve this :)

Thank you.

UPDATE:

So far I have only seen that all of the library for OpenPGP encryption require both the public key and private key to do the encrypt while I only want to encrypt with the public key (because I don't have the private key to use it)!