Java tutorial
/* * Copyright 2012 The Netty Project * * The Netty Project licenses this file to you 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 io.netty.handler.codec.bytes; import io.netty.buffer.ByteBuf; import io.netty.buffer.ByteBufUtil; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelPipeline; import io.netty.handler.codec.LengthFieldBasedFrameDecoder; import io.netty.handler.codec.LengthFieldPrepender; import io.netty.handler.codec.MessageToMessageDecoder; import java.util.List; /** * Decodes a received {@link ByteBuf} into an array of bytes. * A typical setup for TCP/IP would be: * <pre> * {@link ChannelPipeline} pipeline = ...; * * // Decoders * pipeline.addLast("frameDecoder", * new {@link LengthFieldBasedFrameDecoder}(1048576, 0, 4, 0, 4)); * pipeline.addLast("bytesDecoder", * new {@link ByteArrayDecoder}()); * * // Encoder * pipeline.addLast("frameEncoder", new {@link LengthFieldPrepender}(4)); * pipeline.addLast("bytesEncoder", new {@link ByteArrayEncoder}()); * </pre> * and then you can use an array of bytes instead of a {@link ByteBuf} * as a message: * <pre> * void channelRead({@link ChannelHandlerContext} ctx, byte[] bytes) { * ... * } * </pre> */ public class ByteArrayDecoder extends MessageToMessageDecoder<ByteBuf> { @Override protected void decode(ChannelHandlerContext ctx, ByteBuf msg, List<Object> out) throws Exception { // copy the ByteBuf content to a byte array out.add(ByteBufUtil.getBytes(msg)); } }