code: public final boolean verifySignature(PublicKey publicKey) throws GeneralSecurityException {
      Signature signatureAlg = null;
      String algorithm = getHeader().getAlgorithm();
      if ("RS256".equals(algorithm)) {
        signatureAlg = SecurityUtils.getSha256WithRsaSignatureAlgorithm();
      } else {
        return false;
      }
      return SecurityUtils.verify(signatureAlg, publicKey, signatureBytes, signedContentBytes);
    }
docs: Verifies the signature of the content.
  
  <p>Currently only {@code "RS256"} algorithm is verified, but others may be added in the future.
  For any other algorithm it returns {@code false}.
  
  @param publicKey public key
  @return whether the algorithm is recognized and it is verified
  @throws GeneralSecurityException