FileServerHandler.java

/*
 * 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 com.phei.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
 * @date 2014年3月9日
 * @version 1.0
 */
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.ChannelHandlerAdapter#exceptionCaught(io.netty.channel
     * .ChannelHandlerContext, java.lang.Throwable)
     */
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause)
	    throws Exception {
	cause.printStackTrace();
	ctx.close();
    }
}