Java tutorial
/* * This file is part of SpongeClean, licensed under the MIT License (MIT). * * Copyright (c) The VoxelBox <http://thevoxelbox.com> * Copyright (c) contributors * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ package org.spongepowered.clean.network.netty; import io.netty.buffer.ByteBuf; import io.netty.buffer.Unpooled; import io.netty.channel.ChannelHandlerContext; import io.netty.handler.codec.ByteToMessageDecoder; import java.util.List; import java.util.zip.Inflater; import org.spongepowered.clean.util.ByteBufUtil; public class PacketDecompressor extends ByteToMessageDecoder { private final Inflater inflator = new Inflater(); private byte[] inputBuffer = new byte[1024]; public PacketDecompressor() { } @Override protected void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) throws Exception { if (in.readableBytes() == 0) { return; } int length = ByteBufUtil.readVarInt(in); if (length == 0) { // not compressed out.add(in.readBytes(in.readableBytes())); return; } int inputLength = in.readableBytes(); if (this.inputBuffer.length < inputLength) { this.inputBuffer = new byte[inputLength]; } in.readBytes(this.inputBuffer, 0, inputLength); byte[] data = new byte[length]; this.inflator.setInput(this.inputBuffer, 0, inputLength); this.inflator.inflate(data); this.inflator.reset(); // can't use a cached array for the data as the packets will likely be handled asynchronously out.add(Unpooled.wrappedBuffer(data)); } }