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 1.7. 
package org.bouncycastle.asn1.x509;

import org.bouncycastle.asn1.DERInteger;

import java.math.BigInteger;


The CRLNumber object.

CRLNumber::= INTEGER(0..MAX)



/**
 * The CRLNumber object.
 * <pre>
 * CRLNumber::= INTEGER(0..MAX)
 * </pre>
 */
public class CRLNumber
    extends DERInteger
{

    public CRLNumber(
        BigInteger number)
    {
        super(number);
    }

    public BigInteger getCRLNumber()
    {
        return getPositiveValue();
    }

    public String toString()
    {
        return "CRLNumber: " + getCRLNumber();
    }
}