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.
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package org.bouncycastle.crypto.params;

import org.bouncycastle.crypto.CipherParameters;


Public parameters for an SM2 key exchange. In this case the ephemeralPublicKey provides the random point used in the algorithm.

/**
 * Public parameters for an SM2 key exchange. In this case the ephemeralPublicKey provides the random point used in the algorithm.
 */
public class SM2KeyExchangePublicParameters
    implements CipherParameters
{
    private final ECPublicKeyParameters staticPublicKey;
    private final ECPublicKeyParameters ephemeralPublicKey;

    public SM2KeyExchangePublicParameters(
        ECPublicKeyParameters   staticPublicKey,
        ECPublicKeyParameters   ephemeralPublicKey)
    {
        if (staticPublicKey == null)
        {
            throw new NullPointerException("staticPublicKey cannot be null");
        }
        if (ephemeralPublicKey == null)
        {
            throw new NullPointerException("ephemeralPublicKey cannot be null");
        }
        if (!staticPublicKey.getParameters().equals(ephemeralPublicKey.getParameters()))
        {
            throw new IllegalArgumentException("Static and ephemeral public keys have different domain parameters");
        }

        this.staticPublicKey = staticPublicKey;
        this.ephemeralPublicKey = ephemeralPublicKey;
    }

    public ECPublicKeyParameters getStaticPublicKey()
    {
        return staticPublicKey;
    }

    public ECPublicKeyParameters getEphemeralPublicKey()
    {
        return ephemeralPublicKey;
    }
}