util.NettyMessageDecoder.java Source code

Introduction

Here is the source code for util.NettyMessageDecoder.java

Source

package util;

import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.LengthFieldBasedFrameDecoder;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

/*
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/**
 *
 * @author allen
 */
public class NettyMessageDecoder extends LengthFieldBasedFrameDecoder {

    MarshallingDecoder marshallingDecoder;

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

    @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> attach = 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");
                attach.put(key, marshallingDecoder.decode(frame));
            }

            keyArray = null;
            key = null;
            header.setAttachment(attach);
        }

        if (frame.readableBytes() > 4) {
            message.setBody(marshallingDecoder.decode(frame));
        }

        message.setHeader(header);
        return message;
    } //decode()

} //NettyMessageDecoder