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/** * Copyright (C) 2010-2013 Alibaba Group Holding Limited * * 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.alibaba.rocketmq.remoting.netty; import io.netty.buffer.ByteBuf; import io.netty.channel.ChannelHandlerContext; import io.netty.handler.codec.LengthFieldBasedFrameDecoder; import java.nio.ByteBuffer; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.alibaba.rocketmq.remoting.common.RemotingHelper; import com.alibaba.rocketmq.remoting.common.RemotingUtil; import com.alibaba.rocketmq.remoting.protocol.RemotingCommand; /** * @author shijia.wxr<vintage.wang@gmail.com> * @since 2013-7-13 */ public class NettyDecoder extends LengthFieldBasedFrameDecoder { private static final Logger log = LoggerFactory.getLogger(RemotingHelper.RemotingLogName); private static final int FRAME_MAX_LENGTH = // Integer.parseInt(System.getProperty("com.rocketmq.remoting.frameMaxLength", "8388608")); public NettyDecoder() { super(FRAME_MAX_LENGTH, 0, 4, 0, 4); } @Override public Object decode(ChannelHandlerContext ctx, ByteBuf in) throws Exception { ByteBuf frame = null; try { frame = (ByteBuf) super.decode(ctx, in); if (null == frame) { return null; } ByteBuffer byteBuffer = frame.nioBuffer(); return RemotingCommand.decode(byteBuffer); } catch (Exception e) { log.error("decode exception, " + RemotingHelper.parseChannelRemoteAddr(ctx.channel()), e); RemotingUtil.closeChannel(ctx.channel()); } finally { if (null != frame) { frame.release(); } } return null; } }