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.bc;

import org.bouncycastle.asn1.cms.IssuerAndSerialNumber;
import org.bouncycastle.cert.X509CertificateHolder;
import org.bouncycastle.cms.KeyTransRecipientInfoGenerator;
import org.bouncycastle.operator.bc.BcAsymmetricKeyWrapper;

public abstract class BcKeyTransRecipientInfoGenerator
    extends KeyTransRecipientInfoGenerator
{
    public BcKeyTransRecipientInfoGenerator(X509CertificateHolder recipientCert, BcAsymmetricKeyWrapper wrapper)
    {
        super(new IssuerAndSerialNumber(recipientCert.toASN1Structure()), wrapper);
    }

    public BcKeyTransRecipientInfoGenerator(byte[] subjectKeyIdentifier, BcAsymmetricKeyWrapper wrapper)
    {
        super(subjectKeyIdentifier, wrapper);
    }
}