http://www.bouncycastle.org/java.html: The Bouncy Castle Crypto package is a Java implementation of cryptographic algorithms. This jar contains JCE provider and lightweight API for the Bouncy Castle Cryptography APIs for JDK 1.5 to JDK 1.8.
  • The Legion of the Bouncy Castle Inc. 
package org.bouncycastle.jcajce.provider.asymmetric.x509;

import java.security.cert.CRLException;

class ExtCRLException
    extends CRLException
{
    Throwable cause;

    ExtCRLException(String message, Throwable cause)
    {
        super(message);
        this.cause = cause;
    }

    public Throwable getCause()
    {
        return cause;
    }
}