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.pkcs;

import org.bouncycastle.asn1.ASN1OctetString;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.pkcs.ContentInfo;
import org.bouncycastle.asn1.pkcs.PKCSObjectIdentifiers;
import org.bouncycastle.asn1.pkcs.SafeBag;
import org.bouncycastle.cms.CMSEncryptedData;
import org.bouncycastle.cms.CMSException;
import org.bouncycastle.operator.InputDecryptorProvider;

public class PKCS12SafeBagFactory
{
    private ASN1Sequence safeBagSeq;

    public PKCS12SafeBagFactory(ContentInfo info)
    {
        if (info.getContentType().equals(PKCSObjectIdentifiers.encryptedData))
        {
            throw new IllegalArgumentException("encryptedData requires constructor with decryptor.");
        }

        this.safeBagSeq = ASN1Sequence.getInstance(ASN1OctetString.getInstance(info.getContent()).getOctets());
    }

    public PKCS12SafeBagFactory(ContentInfo info, InputDecryptorProvider inputDecryptorProvider)
        throws PKCSException
    {
        if (info.getContentType().equals(PKCSObjectIdentifiers.encryptedData))
        {
            CMSEncryptedData encData = new CMSEncryptedData(org.bouncycastle.asn1.cms.ContentInfo.getInstance(info));

            try
            {
                this.safeBagSeq = ASN1Sequence.getInstance(encData.getContent(inputDecryptorProvider));
            }
            catch (CMSException e)
            {
                throw new PKCSException("unable to extract data: " + e.getMessage(), e);
            }
            return;
        }

        throw new IllegalArgumentException("encryptedData requires constructor with decryptor.");
    }

    public PKCS12SafeBag[] getSafeBags()
    {
        PKCS12SafeBag[] safeBags = new PKCS12SafeBag[safeBagSeq.size()];

        for (int i = 0; i != safeBagSeq.size(); i++)
        {
            safeBags[i] = new PKCS12SafeBag(SafeBag.getInstance(safeBagSeq.getObjectAt(i)));
        }

        return safeBags;
    }
}