de.felix_klauke.pegasus.protocol.decoder.PacketDecoder.java Source code

Introduction

Here is the source code for de.felix_klauke.pegasus.protocol.decoder.PacketDecoder.java

Source

/*
 * Copyright 2016 Felix Klauke
 *
 * 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 de.felix_klauke.pegasus.protocol.decoder;

import de.felix_klauke.pegasus.protocol.Packet;
import de.felix_klauke.pegasus.protocol.PacketType;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.EmptyByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.ByteToMessageDecoder;
import io.netty.handler.codec.UnsupportedMessageTypeException;

import java.util.List;

/**
 * Created by Felix Klauke for project Pegasus on 14.02.2016.
 */
public class PacketDecoder extends ByteToMessageDecoder {

    /* ----------------------------------- [ Method ] ----------------------------------- */

    /**
     * This method will handle any incoming data. Neverminds about the type.
     *
     * @param channelHandlerContext the contect of the Channel the data comes from
     * @param byteBuf               the incoming data
     * @param list                  add all objects to continue to work with to this list
     * @throws Exception will be thrown when handling the data fails
     */
    @Override
    protected void decode(ChannelHandlerContext channelHandlerContext, ByteBuf byteBuf, List<Object> list)
            throws Exception {
        if (byteBuf instanceof EmptyByteBuf)
            return;
        int packetID = byteBuf.readInt();

        if (packetID == -1) {
            throw new UnsupportedMessageTypeException();
        }
        Packet packet = PacketType.lookup(packetID);
        if (packet != null) {
            packet.decode(byteBuf);
            list.add(packet);
        }
    }

}