如何控制netty使用什么缓冲区进行读操作？

// 使用PooledByteBufAllocator
Bootstrap bootstrap = new Bootstrap();
bootstrap.group(eventLoopGroup)
    .channel(NioSocketChannel.class)
    .option(ChannelOption.ALLOCATOR, PooledByteBufAllocator.DEFAULT)
    .handler(new ChannelInitializer<SocketChannel>() {
        @Override
        protected void initChannel(SocketChannel ch) throws Exception {
            // 添加处理器
        }
    });

// 使用UnpooledByteBufAllocator
Bootstrap bootstrap = new Bootstrap();
bootstrap.group(eventLoopGroup)
    .channel(NioSocketChannel.class)
    .option(ChannelOption.ALLOCATOR, UnpooledByteBufAllocator.DEFAULT)
    .handler(new ChannelInitializer<SocketChannel>() {
        @Override
        protected void initChannel(SocketChannel ch) throws Exception {
            // 添加处理器
        }
    });