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. 
package org.bouncycastle.asn1.icao;

import java.util.Enumeration;

import org.bouncycastle.asn1.ASN1Encodable;
import org.bouncycastle.asn1.ASN1EncodableVector;
import org.bouncycastle.asn1.ASN1OctetString;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.DERInteger;
import org.bouncycastle.asn1.DERObject;
import org.bouncycastle.asn1.DERSequence;


The DataGroupHash object.

DataGroupHash  ::=  SEQUENCE {
     dataGroupNumber         DataGroupNumber,
     dataGroupHashValue     OCTET STRING }
DataGroupNumber ::= INTEGER {
        dataGroup1    (1),
        dataGroup1    (2),
        dataGroup1    (3),
        dataGroup1    (4),
        dataGroup1    (5),
        dataGroup1    (6),
        dataGroup1    (7),
        dataGroup1    (8),
        dataGroup1    (9),
        dataGroup1    (10),
        dataGroup1    (11),
        dataGroup1    (12),
        dataGroup1    (13),
        dataGroup1    (14),
        dataGroup1    (15),
        dataGroup1    (16) }



/**
 * The DataGroupHash object.
 * <pre>
 * DataGroupHash  ::=  SEQUENCE {
 *      dataGroupNumber         DataGroupNumber,
 *      dataGroupHashValue     OCTET STRING }
 * 
 * DataGroupNumber ::= INTEGER {
 *         dataGroup1    (1),
 *         dataGroup1    (2),
 *         dataGroup1    (3),
 *         dataGroup1    (4),
 *         dataGroup1    (5),
 *         dataGroup1    (6),
 *         dataGroup1    (7),
 *         dataGroup1    (8),
 *         dataGroup1    (9),
 *         dataGroup1    (10),
 *         dataGroup1    (11),
 *         dataGroup1    (12),
 *         dataGroup1    (13),
 *         dataGroup1    (14),
 *         dataGroup1    (15),
 *         dataGroup1    (16) }
 * 
 * </pre>
 */
public class DataGroupHash 
    extends ASN1Encodable
{
    DERInteger dataGroupNumber;    
    ASN1OctetString    dataGroupHashValue;
    
    public static DataGroupHash getInstance(
        Object obj)
    {
        if (obj instanceof DataGroupHash)
        {
            return (DataGroupHash)obj;
        }
        else if (obj != null)
        {
            return new DataGroupHash(ASN1Sequence.getInstance(obj));
        }

        return null;
    }                
            
    private DataGroupHash(ASN1Sequence seq)
    {
        Enumeration e = seq.getObjects();

        // dataGroupNumber
        dataGroupNumber = DERInteger.getInstance(e.nextElement());
        // dataGroupHashValue
        dataGroupHashValue = ASN1OctetString.getInstance(e.nextElement());   
    }
    
    public DataGroupHash(
        int dataGroupNumber,        
        ASN1OctetString     dataGroupHashValue)
    {
        this.dataGroupNumber = new DERInteger(dataGroupNumber);
        this.dataGroupHashValue = dataGroupHashValue; 
    }    

    public int getDataGroupNumber()
    {
        return dataGroupNumber.getValue().intValue();
    }
    
    public ASN1OctetString getDataGroupHashValue()
    {
        return dataGroupHashValue;
    }     
    
    public DERObject toASN1Object() 
    {
        ASN1EncodableVector seq = new ASN1EncodableVector();
        seq.add(dataGroupNumber);
        seq.add(dataGroupHashValue);  

        return new DERSequence(seq);
    }
}