code: public static Algorithm ECDSA512(ECPublicKey publicKey, ECPrivateKey privateKey) throws IllegalArgumentException {
          return ECDSA512(ECDSAAlgorithm.providerForKeys(publicKey, privateKey));
      }
docs: Creates a new Algorithm instance using SHA512withECDSA. Tokens specify this as "ES512".
  
  @param publicKey  the key to use in the verify instance.
  @param privateKey the key to use in the signing instance.
  @return a valid ECDSA512 Algorithm.
  @throws IllegalArgumentException if the provided Key is null.