import org.bitcoinj.net.NioClient; //导入依赖的package包/类
/**
 * Attempts to open a new connection to and open a payment channel with the given host and port, blocking until the
 * connection is open.  The server is requested to keep the channel open for {@param timeWindow}
 * seconds. If the server proposes a longer time the channel will be closed.
 *
 * @param server The host/port pair where the server is listening.
 * @param timeoutSeconds The connection timeout and read timeout during initialization. This should be large enough
 *                       to accommodate ECDSA signature operations and network latency.
 * @param wallet The wallet which will be paid from, and where completed transactions will be committed.
 *               Must already have a {@link StoredPaymentChannelClientStates} object in its extensions set.
 * @param myKey A freshly generated keypair used for the multisig contract and refund output.
 * @param maxValue The maximum value this channel is allowed to request
 * @param serverId A unique ID which is used to attempt reopening of an existing channel.
 *                 This must be unique to the server, and, if your application is exposing payment channels to some
 *                 API, this should also probably encompass some caller UID to avoid applications opening channels
 *                 which were created by others.
 * @param timeWindow The time in seconds, relative to now, on how long this channel should be kept open.
 *
 * @throws IOException if there's an issue using the network.
 * @throws ValueOutOfRangeException if the balance of wallet is lower than maxValue.
 */
public PaymentChannelClientConnection(InetSocketAddress server, int timeoutSeconds, Wallet wallet, ECKey myKey,
                                      Coin maxValue, String serverId, final long timeWindow) throws IOException, ValueOutOfRangeException {
    // Glue the object which vends/ingests protobuf messages in order to manage state to the network object which
    // reads/writes them to the wire in length prefixed form.
    channelClient = new PaymentChannelClient(wallet, myKey, maxValue, Sha256Hash.create(serverId.getBytes()), timeWindow,
          new PaymentChannelClient.ClientConnection() {
        @Override
        public void sendToServer(Protos.TwoWayChannelMessage msg) {
            wireParser.write(msg);
        }

        @Override
        public void destroyConnection(PaymentChannelCloseException.CloseReason reason) {
            channelOpenFuture.setException(new PaymentChannelCloseException("Payment channel client requested that the connection be closed: " + reason, reason));
            wireParser.closeConnection();
        }

        @Override
        public boolean acceptExpireTime(long expireTime) {
            return expireTime <= (timeWindow + Utils.currentTimeSeconds() + 60);  // One extra minute to compensate for time skew and latency
        }

        @Override
        public void channelOpen(boolean wasInitiated) {
            wireParser.setSocketTimeout(0);
            // Inform the API user that we're done and ready to roll.
            channelOpenFuture.set(PaymentChannelClientConnection.this);
        }
    });

    // And glue back in the opposite direction - network to the channelClient.
    wireParser = new ProtobufParser<Protos.TwoWayChannelMessage>(new ProtobufParser.Listener<Protos.TwoWayChannelMessage>() {
        @Override
        public void messageReceived(ProtobufParser<Protos.TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
            try {
                channelClient.receiveMessage(msg);
            } catch (InsufficientMoneyException e) {
                // We should only get this exception during INITIATE, so channelOpen wasn't called yet.
                channelOpenFuture.setException(e);
            }
        }

        @Override
        public void connectionOpen(ProtobufParser<Protos.TwoWayChannelMessage> handler) {
            channelClient.connectionOpen();
        }

        @Override
        public void connectionClosed(ProtobufParser<Protos.TwoWayChannelMessage> handler) {
            channelClient.connectionClosed();
            channelOpenFuture.setException(new PaymentChannelCloseException("The TCP socket died",
                    PaymentChannelCloseException.CloseReason.CONNECTION_CLOSED));
        }
    }, Protos.TwoWayChannelMessage.getDefaultInstance(), Short.MAX_VALUE, timeoutSeconds*1000);

    // Initiate the outbound network connection. We don't need to keep this around. The wireParser object will handle
    // things from here on out.
    new NioClient(server, wireParser, timeoutSeconds * 1000);
}