hi,I see the  code for method setBytes in class com.alibaba.dubbo.remoting.transport.netty4.NettyBackedChannelBuffer.java which is below,is there a problem ?

![image](https://user-images.githubusercontent.com/20593632/46648646-90eaba00-cbc8-11e8-896d-9a1d235d7e0b.png)


@Override
    public ByteBuffer toByteBuffer(int index, int length) {
        return buffer.nioBuffer(index, length);
    }
    
    @Override
    public byte[] array() {
        return buffer.array();
    }
    
    @Override
    public boolean hasArray() {
        return buffer.hasArray();
    }
    
    @Override
    public int arrayOffset() {
        return buffer.arrayOffset();
    }
    
    
    @Override
    public void clear() {
        buffer.clear();
    }
    
    @Override
    public ChannelBuffer copy() {
        return new NettyBackedChannelBuffer(buffer.copy());
    }