books.netty.protocol.file.FileServerHandler.java Source code

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Here is the source code for books.netty.protocol.file.FileServerHandler.java

Source

/*
 * Copyright 2013-2018 Lilinfeng.
 *  
 * Licensed 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 books.netty.protocol.file;

import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.DefaultFileRegion;
import io.netty.channel.FileRegion;
import io.netty.channel.SimpleChannelInboundHandler;

import java.io.File;
import java.io.RandomAccessFile;

/**
 * @author Administrator
 * @version 1.0
 * @date 201439
 */
public class FileServerHandler extends SimpleChannelInboundHandler<String> {

    private static final String CR = System.getProperty("line.separator");

    /*
     * (non-Javadoc)
     *
     * @see
     * io.netty.channel.SimpleChannelInboundHandler#messageReceived(io.netty
     * .channel.ChannelHandlerContext, java.lang.Object)
     */
    public void messageReceived(ChannelHandlerContext ctx, String msg) throws Exception {
        File file = new File(msg);
        if (file.exists()) {
            if (!file.isFile()) {
                ctx.writeAndFlush("Not a file : " + file + CR);
                return;
            }
            ctx.write(file + " " + file.length() + CR);
            RandomAccessFile randomAccessFile = new RandomAccessFile(msg, "r");
            FileRegion region = new DefaultFileRegion(randomAccessFile.getChannel(), 0, randomAccessFile.length());
            ctx.write(region);
            ctx.writeAndFlush(CR);
            randomAccessFile.close();
        } else {
            ctx.writeAndFlush("File not found: " + file + CR);
        }
    }

    /*
     * (non-Javadoc)
     *
     * @see
     * io.netty.channel.ChannelInboundHandlerAdapter#exceptionCaught(io.netty.channel
     * .ChannelHandlerContext, java.lang.Throwable)
     */
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
        cause.printStackTrace();
        ctx.close();
    }

    @Override
    protected void channelRead0(ChannelHandlerContext ctx, String msg) {
        // todo
    }
}