@AccessesPartialKey
  static RsaSsaPkcs1PublicKey toRsaSsaPkcs1PublicKey(JwtRsaSsaPkcs1PublicKey publicKey)
      throws GeneralSecurityException {
    RsaSsaPkcs1Parameters rsaSsaPkcs1Parameters =
        RsaSsaPkcs1Parameters.builder()
            .setModulusSizeBits(publicKey.getParameters().getModulusSizeBits())
            .setPublicExponent(publicKey.getParameters().getPublicExponent())
            .setHashType(hashTypeForAlgorithm(publicKey.getParameters().getAlgorithm()))
            .setVariant(RsaSsaPkcs1Parameters.Variant.NO_PREFIX)
            .build();
    return RsaSsaPkcs1PublicKey.builder()
        .setParameters(rsaSsaPkcs1Parameters)
        .setModulus(publicKey.getModulus())
        .build();
  }
This key manager produces new instances of {@code JwtRsaSsaPkcs11Verify}. It doesn't support key
generation.
java_src/src/main/java/com/google/crypto/tink/jwt/JwtRsaSsaPkcs1VerifyKeyManager.java