com.ldp.nettydemo.netty.codec.NettyMessageDecoder.java Source code

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Here is the source code for com.ldp.nettydemo.netty.codec.NettyMessageDecoder.java

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/*
 * 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.ldp.nettydemo.netty.codec;

import com.ldp.nettydemo.netty.struct.Header;
import com.ldp.nettydemo.netty.struct.NettyMessage;
import com.ldp.nettydemo.netty.util.ByteBufToBytes;
import com.ldp.nettydemo.netty.util.ByteObjConverter;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.LengthFieldBasedFrameDecoder;

/**
 * @author Lilinfeng
 * @date 2014315
 * @version 1.0
 */
public class NettyMessageDecoder extends LengthFieldBasedFrameDecoder {

    //    MarshallingDecoder marshallingDecoder;

    public NettyMessageDecoder(int maxFrameLength, int lengthFieldOffset, int lengthFieldLength)
            throws IOException {
        super(maxFrameLength, lengthFieldOffset, lengthFieldLength);
        //   marshallingDecoder = new MarshallingDecoder();
    }

    @Override
    protected Object decode(ChannelHandlerContext ctx, ByteBuf in) throws Exception {
        ByteBuf frame = (ByteBuf) super.decode(ctx, in);
        if (frame == null) {
            return null;
        }

        NettyMessage message = new NettyMessage();
        Header header = new Header();
        header.setCrcCode(frame.readInt());
        header.setLength(frame.readInt());
        header.setSessionID(frame.readLong());
        header.setType(frame.readByte());
        header.setPriority(frame.readByte());

        int size = frame.readInt();
        if (size > 0) {
            Map<String, Object> attch = new HashMap<String, Object>(size);
            int keySize = 0;
            byte[] keyArray = null;
            String key = null;
            for (int i = 0; i < size; i++) {
                keySize = frame.readInt();
                keyArray = new byte[keySize];
                frame.readBytes(keyArray);
                key = new String(keyArray, "UTF-8");
                attch.put(key, ByteObjConverter.ByteToObject(new ByteBufToBytes().read(frame)));
                //      attch.put(key, marshallingDecoder.decode(frame));
            }
            keyArray = null;
            key = null;
            header.setAttachment(attch);
        }
        if (frame.readableBytes() > 4) {
            message.setBody(ByteObjConverter.ByteToObject(new ByteBufToBytes().read(frame)));
            //       message.setBody(marshallingDecoder.decode(frame));
        }
        message.setHeader(header);
        return message;
    }
}