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/*
 * Copyright 2012 The Netty Project
 *
 * The Netty Project licenses this file to you under the Apache License,
 * version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */
package io.netty.example.telnet;

import io.netty.bootstrap.Bootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioSocketChannel;

import java.io.BufferedReader;
import java.io.InputStreamReader;

/**
 * Simplistic telnet client.
 */
public class TelnetClient {

    private final String host;
    private final int port;

    public TelnetClient(String host, int port) {
        this.host = host;
        this.port = port;
    }

    public void run() throws Exception {
        Bootstrap b = new Bootstrap();
        try {
            b.group(new NioEventLoopGroup())
             .channel(NioSocketChannel.class)
             .handler(new TelnetClientInitializer());

            // Start the connection attempt.
            Channel ch = b.connect(host, port).sync().channel();

            // Read commands from the stdin.
            ChannelFuture lastWriteFuture = null;
            BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
            for (;;) {
                String line = in.readLine();
                if (line == null) {
                    break;
                }

                // Sends the received line to the server.
                lastWriteFuture = ch.write(line + "\r\n");

                // If user typed the 'bye' command, wait until the server closes
                // the connection.
                if ("bye".equals(line.toLowerCase())) {
                    ch.closeFuture().sync();
                    break;
                }
            }

            // Wait until all messages are flushed before closing the channel.
            if (lastWriteFuture != null) {
                lastWriteFuture.sync();
            }
        } finally {
            b.shutdown();
        }
    }

    public static void main(String[] args) throws Exception {
        // Print usage if no argument is specified.
        if (args.length != 2) {
            System.err.println(
                    "Usage: " + TelnetClient.class.getSimpleName() +
                    "  ");
            return;
        }

        // Parse options.
        String host = args[0];
        int port = Integer.parseInt(args[1]);

        new TelnetClient(host, port).run();
    }
}