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.cert.path;

import org.bouncycastle.cert.X509CertificateHolder;

public class CertPath
{
    private final X509CertificateHolder[] certificates;

    public CertPath(X509CertificateHolder[] certificates)
    {
        this.certificates = copyArray(certificates);
    }

    public X509CertificateHolder[] getCertificates()
    {
        return copyArray(certificates);
    }

    public CertPathValidationResult validate(CertPathValidation[] ruleSet)
    {
        CertPathValidationContext context = new CertPathValidationContext(CertPathUtils.getCriticalExtensionsOIDs(certificates));

        for (int i = 0; i != ruleSet.length; i++)
        {
            for (int j = certificates.length - 1; j >= 0; j--)
            {
                try
                {
                    context.setIsEndEntity(j == 0);
                    ruleSet[i].validate(context, certificates[j]);
                }
                catch (CertPathValidationException e)
                {   // TODO: introduce object to hold (i and e)
                    return new CertPathValidationResult(context, j, i, e);
                }
            }
        }

        return new CertPathValidationResult(context);
    }

    public CertPathValidationResult evaluate(CertPathValidation[] ruleSet)
    {
        CertPathValidationContext context = new CertPathValidationContext(CertPathUtils.getCriticalExtensionsOIDs(certificates));

        CertPathValidationResultBuilder builder = new CertPathValidationResultBuilder(context);

        for (int i = 0; i != ruleSet.length; i++)
        {
            for (int j = certificates.length - 1; j >= 0; j--)
            {
                try
                {
                    context.setIsEndEntity(j == 0);
                    ruleSet[i].validate(context, certificates[j]);
                }
                catch (CertPathValidationException e)
                {
                   builder.addException(j, i, e);
                }
            }
        }

        return builder.build();
    }

    private X509CertificateHolder[] copyArray(X509CertificateHolder[] array)
    {
        X509CertificateHolder[] rv = new X509CertificateHolder[array.length];

        System.arraycopy(array, 0, rv, 0, rv.length);

        return rv;
    }

    public int length()
    {
        return certificates.length;
    }
}