init method

Implementation

@override
void init(CipherParameters params) {
  var akparams = params as AsymmetricKeyParameter<AsymmetricKey>;
  var k = akparams.key as ECAsymmetricKey;
  if (k is! ECPrivateKey) {
    throw ArgumentError('ECPrivateKey is required for decryption.');
  }
  _key = k;
}