我在扩展ReplayingDecoder的DecodeEventHandler类中遇到ResourceLeakDetector异常。我很难理解何时何地应该释放任何方法的BytBuf。我是否需要释放传递的ByteBuf？我尝试释放header，eventBody和attachedData ByteBuf对象，但后来在我的代码中创建了问题。代码是......
protected void decode(ChannelHandlerContext channelHandlerContext, ByteBuf byteBuf, List<Object> list) throws Exception
{
switch (state())
{
case READ_HEADER:
ByteBuf header = byteBuf.readBytes(BaseEvent.EVENT_HEADER_SIZE);
newEvent = new BaseEvent(header.nioBuffer());
checkpoint(EventDecoderState.READ_BODY);
// Fall through
case READ_BODY:
ByteBuf eventBody = byteBuf.readBytes(newEvent.getEventHeaderBodySize() - BaseEvent.EVENT_HEADER_SIZE);
newEvent.setEventBody(eventBody.nioBuffer());
checkpoint(EventDecoderState.READ_ATTACHED_DATA);
// Fall through
case READ_ATTACHED_DATA:
ByteBuf attachedData = byteBuf.readBytes(newEvent.getAttachedDataSize());
newEvent.clearAttachedData();
newEvent.addAttachedData(attachedData.nioBuffer());
list.add(newEvent);
checkpoint(EventDecoderState.READ_HEADER);
}
}
该方法从第23行开始。我收到的例外是......
2016-06-07 13:30:49.783 [ERROR] (nioEventLoopGroup-7-1) io.netty.util.ResourceLeakDetector - LEAK: ByteBuf.release() was not called before it's garbage-collected. See http://netty.io/wiki/reference-counted-objects.html for more information.
Recent access records: 2
#2:
io.netty.buffer.AdvancedLeakAwareByteBuf.nioBuffer(AdvancedLeakAwareByteBuf.java:669)
com.oakgate.netty.DecodeEventHandler.decode(DecodeEventHandler.java:30)
io.netty.handler.codec.ReplayingDecoder.callDecode(ReplayingDecoder.java:376)
io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:245)
io.netty.channel.ChannelHandlerInvokerUtil.invokeChannelReadNow(ChannelHandlerInvokerUtil.java:83)
io.netty.channel.DefaultChannelHandlerInvoker.invokeChannelRead(DefaultChannelHandlerInvoker.java:154)
io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:354)
io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:145)
io.netty.channel.ChannelInboundHandlerAdapter.channelRead(ChannelInboundHandlerAdapter.java:86)
io.netty.channel.ChannelHandlerInvokerUtil.invokeChannelReadNow(ChannelHandlerInvokerUtil.java:83)
io.netty.channel.DefaultChannelHandlerInvoker.invokeChannelRead(DefaultChannelHandlerInvoker.java:154)
io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:354)
io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:145)
io.netty.handler.timeout.IdleStateHandler.channelRead(IdleStateHandler.java:266)
io.netty.channel.ChannelHandlerInvokerUtil.invokeChannelReadNow(ChannelHandlerInvokerUtil.java:83)
io.netty.channel.DefaultChannelHandlerInvoker.invokeChannelRead(DefaultChannelHandlerInvoker.java:154)
io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:354)
io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:145)
io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:1078)
io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:117)
io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:527)
io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:484)
io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:398)
io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:370)
io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:742)
io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:145)
java.lang.Thread.run(Thread.java:745)
#1:
io.netty.buffer.AdvancedLeakAwareByteBuf.writeBytes(AdvancedLeakAwareByteBuf.java:561)
io.netty.buffer.AbstractByteBuf.readBytes(AbstractByteBuf.java:790)
io.netty.handler.codec.ReplayingDecoderByteBuf.readBytes(ReplayingDecoderByteBuf.java:576)
com.oakgate.netty.DecodeEventHandler.decode(DecodeEventHandler.java:29)
io.netty.handler.codec.ReplayingDecoder.callDecode(ReplayingDecoder.java:376)
io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:245)
io.netty.channel.ChannelHandlerInvokerUtil.invokeChannelReadNow(ChannelHandlerInvokerUtil.java:83)
io.netty.channel.DefaultChannelHandlerInvoker.invokeChannelRead(DefaultChannelHandlerInvoker.java:154)
io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:354)
io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:145)
io.netty.channel.ChannelInboundHandlerAdapter.channelRead(ChannelInboundHandlerAdapter.java:86)
io.netty.channel.ChannelHandlerInvokerUtil.invokeChannelReadNow(ChannelHandlerInvokerUtil.java:83)
io.netty.channel.DefaultChannelHandlerInvoker.invokeChannelRead(DefaultChannelHandlerInvoker.java:154)
io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:354)
io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:145)
io.netty.handler.timeout.IdleStateHandler.channelRead(IdleStateHandler.java:266)
io.netty.channel.ChannelHandlerInvokerUtil.invokeChannelReadNow(ChannelHandlerInvokerUtil.java:83)
io.netty.channel.DefaultChannelHandlerInvoker.invokeChannelRead(DefaultChannelHandlerInvoker.java:154)
io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:354)
io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:145)
io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:1078)
io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:117)
io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:527)
io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:484)
io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:398)
io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:370)
io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:742)
io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:145)
java.lang.Thread.run(Thread.java:745)
Created at:
io.netty.buffer.PooledByteBufAllocator.newDirectBuffer(PooledByteBufAllocator.java:271)
io.netty.buffer.AbstractByteBufAllocator.directBuffer(AbstractByteBufAllocator.java:179)
io.netty.buffer.AbstractByteBufAllocator.buffer(AbstractByteBufAllocator.java:115)
io.netty.buffer.AbstractByteBuf.readBytes(AbstractByteBuf.java:789)
io.netty.handler.codec.ReplayingDecoderByteBuf.readBytes(ReplayingDecoderByteBuf.java:576)
com.oakgate.netty.DecodeEventHandler.decode(DecodeEventHandler.java:29)
io.netty.handler.codec.ReplayingDecoder.callDecode(ReplayingDecoder.java:376)
io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:245)
io.netty.channel.ChannelHandlerInvokerUtil.invokeChannelReadNow(ChannelHandlerInvokerUtil.java:83)
io.netty.channel.DefaultChannelHandlerInvoker.invokeChannelRead(DefaultChannelHandlerInvoker.java:154)
io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:354)
io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:145)
io.netty.channel.ChannelInboundHandlerAdapter.channelRead(ChannelInboundHandlerAdapter.java:86)
io.netty.channel.ChannelHandlerInvokerUtil.invokeChannelReadNow(ChannelHandlerInvokerUtil.java:83)
io.netty.channel.DefaultChannelHandlerInvoker.invokeChannelRead(DefaultChannelHandlerInvoker.java:154)
io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:354)
io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:145)
io.netty.handler.timeout.IdleStateHandler.channelRead(IdleStateHandler.java:266)
io.netty.channel.ChannelHandlerInvokerUtil.invokeChannelReadNow(ChannelHandlerInvokerUtil.java:83)
io.netty.channel.DefaultChannelHandlerInvoker.invokeChannelRead(DefaultChannelHandlerInvoker.java:154)
io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:354)
io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:145)
io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:1078)
io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:117)
io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:527)
io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:484)
io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:398)
io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:370)
io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:742)
io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:145)
java.lang.Thread.run(Thread.java:745)
其他信息
当我释放由调用byteBuf.readBytes（）（header，eventBody和attachedData）创建的每个ByteBuf时，我会在以后处理事件时遇到问题。我调用nioBuffer（）从ByteBuf创建一个ByteBuffer，看起来释放原始的ByteBuf会影响ioBuffer（）调用的ByteBuffer。根据文档，返回的缓冲区与bytebuf共享内容，这很可能意味着我还不能释放它。我是否需要保留每个ByteBuf，然后在处理事件时释放？除非有其他方法可以做到这一点，否则就会出现这种情况。
答案 0 :(得分：1)
您正在通过ByteBuf创建新的byteBuf.readBytes，需要将其发布。
case READ_HEADER:的示例：
case READ_HEADER:
ByteBuf header = null;
try {
header = byteBuf.readBytes(BaseEvent.EVENT_HEADER_SIZE);
newEvent = new BaseEvent(header.nioBuffer());
checkpoint(EventDecoderState.READ_BODY);
} finally {
if(header != null)
header.release();
}
// Fall through