Java tutorial
//package com.java2s; import java.security.GeneralSecurityException; import java.security.PublicKey; import java.security.cert.X509Certificate; public class Main { protected static void verifyX509Certificate(X509Certificate cert, PublicKey publicKey, String sigProvider) throws GeneralSecurityException { if (sigProvider == null) { cert.verify(publicKey); } else { cert.verify(publicKey, sigProvider); } } }