http://www.bouncycastle.org/java.html: The Bouncy Castle Java APIs for CMS, PKCS, EAC, TSP, CMP, CRMF, OCSP, and certificate generation. This jar contains APIs for JDK 1.5 to JDK 1.8. The APIs can be used in conjunction with a JCE/JCA provider such as the one provided with the Bouncy Castle Cryptography APIs.
  • The Legion of the Bouncy Castle Inc. 
package org.bouncycastle.cms;

public class CMSException
    extends Exception
{
    Exception   e;

    public CMSException(
        String msg)
    {
        super(msg);
    }

    public CMSException(
        String msg,
        Exception e)
    {
        super(msg);

        this.e = e;
    }

    public Exception getUnderlyingException()
    {
        return e;
    }
    
    public Throwable getCause()
    {
        return e;
    }
}