public static Enums.HashType hashForEcdsaAlgorithm(JwtEcdsaAlgorithm algorithm)
      throws GeneralSecurityException {
    switch (algorithm) {
      case ES256:
        return Enums.HashType.SHA256;
      case ES384:
        return Enums.HashType.SHA384;
      case ES512:
        return Enums.HashType.SHA512;
      default:
        throw new GeneralSecurityException("unknown algorithm " + algorithm.name());
    }
  }
This key manager produces new instances of {@code JwtEcdsaVerify}. It doesn't support key
generation.
java_src/src/main/java/com/google/crypto/tink/jwt/JwtEcdsaVerifyKeyManager.java