ReplayingDecoder在解码

时间:2016-05-29 15:19:53

标签: java netty nio

我创建了一个解码器来处理客户端发送的字节。 这是它

import java.util.List;

import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.ReplayingDecoder;

public class MessageDecoder extends ReplayingDecoder<DecoderState> {

    private int length;

    public MessageDecoder()
    {
        super(DecoderState.READ_LENGTH);
    }

    @Override
    protected void decode(ChannelHandlerContext ctx, ByteBuf buf, List<Object> out) throws Exception{
        System.out.println(buf.readableBytes());
        switch(state()){
            case READ_LENGTH:
                length=buf.readInt();
                System.out.println("length is: "+length);
                checkpoint(DecoderState.READ_CONTENT);
            case READ_CONTENT:
                ByteBuf frame = buf.readBytes(length);
                checkpoint(DecoderState.READ_LENGTH);
                out.add(frame);
                break;
            default:
                throw new Error("Shouldn't reach here");
        }
    }
}

当客户端发送字节

时,它会抛出下一个错误
  

io.netty.handler.codec.DecoderException:java.lang.IllegalArgumentException:minimumReadableBytes:-603652096(expected:&gt; = 0)       在io.netty.handler.codec.ReplayingDecoder.callDecode(ReplayingDecoder.java:431)       at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:245)       at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:292)       at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:278)       at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:962)       at io.netty.channel.nio.AbstractNioByteChannel $ NioByteUnsafe.read(AbstractNioByteChannel.java:131)       在io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:528)       at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:485)       at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:399)       在io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:371)       at io.netty.util.concurrent.SingleThreadEventExecutor $ 2.run(SingleThreadEventExecutor.java:112)       at io.netty.util.concurrent.DefaultThreadFactory $ DefaultRunnableDecorator.run(DefaultThreadFactory.java:137)       在java.lang.Thread.run(未知来源)

该代码来自官方文档http://netty.io/4.0/api/io/netty/handler/codec/ReplayingDecoder.html,所以我真的不明白为什么它不起作用

1 个答案:

答案 0 :(得分:1)

远程对等体可能将int写为unsigned。也许你想要的是使用readUnsignedInt()?