com.github.nettybook.ch8.TelnetServerHandler.java Source code

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Here is the source code for com.github.nettybook.ch8.TelnetServerHandler.java

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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 com.github.nettybook.ch8;

import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandler.Sharable;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;

import java.net.InetAddress;
import java.util.Date;

/**
 * Handles a server-side channel.
 */
@Sharable
public class TelnetServerHandler extends SimpleChannelInboundHandler<String> {
    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {
        ctx.write(InetAddress.getLocalHost().getHostName() + " ? ? !\r\n");
        ctx.write(" ? " + new Date() + " .\r\n");
        ctx.flush();
    }

    @Override
    public void channelRead0(ChannelHandlerContext ctx, String request) throws Exception {
        // Generate and write a response.
        String response;
        boolean close = false;
        if (request.isEmpty()) {
            response = "?  .\r\n";
        } else if ("bye".equals(request.toLowerCase())) {
            response = " !\r\n";
            close = true;
        } else {
            response = " ? '" + request + "' .\r\n";
        }

        // TelnetPipelineFactory? ? StringEncoder? ?? ?   
        // ChannelBuffer?  ?    ? ?? .   
        ChannelFuture future = ctx.write(response);

        // ??? bye ?  close  true? ? ? ?.
        if (close) {
            future.addListener(ChannelFutureListener.CLOSE);
        }
    }

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) {
        ctx.flush();
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
        cause.printStackTrace();
        ctx.close();
    }
}