Java

Load a Private Key from a JWK

Demonstrates the Chilkat PrivateKey.LoadJwk method, which loads a private key from JWK (JSON Web Key) JSON. The only argument is the JWK JSON string. Supported key types are RSA, EC, and Ed25519 (kty=OKP).

Background: JWK is the JSON key format used throughout modern web security — JWT signing, OAuth, OpenID Connect — so this loader is what you use to consume a key from a JWK Set or an identity provider. A private JWK includes the private parameters (d and, for RSA, the CRT values); a public-only JWK omits them. As JSON in the clear, a private JWK must be handled as sensitive material.

Chilkat Java Downloads

Download Chilkat for Java

Chilkat2 Java

import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.PrivateKey;

public class ChilkatExample {

    public static void main(String[] args) {
        // Demonstrates the PrivateKey.LoadJwk method, which loads a private key from JWK (JSON Web Key)
        // JSON.  The only argument is the JWK JSON string.  Supported key types are RSA, EC, and
        // Ed25519 (kty=OKP).

        PrivateKey privKey = new PrivateKey();

        // A private JWK.  For a real key, "d" (and the other private parameters) would be present.
        String jwk = "{\"kty\":\"EC\",\"crv\":\"P-256\",\"x\":\"...\",\"y\":\"...\",\"d\":\"...\"}";

        try {
            privKey.loadJwk(jwk);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        System.out.println("Loaded a " + privKey.getKeyType() + " private key.");
    }
}