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 1.8.
  • The Legion of the Bouncy Castle Inc. 
package org.bouncycastle.crypto.params;

import org.bouncycastle.crypto.CipherParameters;

public class AsymmetricKeyParameter
    implements CipherParameters
{
    boolean privateKey;

    public AsymmetricKeyParameter(
        boolean privateKey)
    {
        this.privateKey = privateKey;
    }

    public boolean isPrivate()
    {
        return privateKey;
    }
}