How to use

equals

method

in

org.spongycastle.crypto.params.DHParameters

public boolean equals(
  Object  obj)
{
  if (!(obj instanceof DHKeyParameters))
  {
    return false;
  }
  DHKeyParameters    dhKey = (DHKeyParameters)obj;
  if (params == null)
  {
    return dhKey.getParameters() == null;
  }
  else
  { 
    return params.equals(dhKey.getParameters());
  }
}

public boolean equals(
  Object  obj)
{
  if (!(obj instanceof DHKeyParameters))
  {
    return false;
  }
  DHKeyParameters    dhKey = (DHKeyParameters)obj;
  if (params == null)
  {
    return dhKey.getParameters() == null;
  }
  else
  { 
    return params.equals(dhKey.getParameters());
  }
}

BigInteger              message)
if (!pub.getParameters().equals(dhParams))

if (!pub.getParameters().equals(dhParams))

  /**
   * given a message from a given party and the corresponding public key,
   * calculate the next message in the agreement sequence. In this case
   * this will represent the shared secret.
   */
  public BigInteger calculateAgreement(
    DHPublicKeyParameters   pub,
    BigInteger              message)
  {
    if (!pub.getParameters().equals(dhParams))
    {
      throw new IllegalArgumentException("Diffie-Hellman public key has wrong parameters.");
    }

    BigInteger p = dhParams.getP();

    return message.modPow(key.getX(), p).multiply(pub.getY().modPow(privateValue, p)).mod(p);
  }
}

  /**
   * given a short term public key from a given party calculate the next
   * message in the agreement sequence. 
   */
  public BigInteger calculateAgreement(
    CipherParameters   pubKey)
  {
    DHPublicKeyParameters   pub = (DHPublicKeyParameters)pubKey;

    if (!pub.getParameters().equals(dhParams))
    {
      throw new IllegalArgumentException("Diffie-Hellman public key has wrong parameters.");
    }

    return pub.getY().modPow(key.getX(), dhParams.getP());
  }
}