gistfile1.txt

package io.netty.example.http.snoop;

import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelOutboundHandlerAdapter;
import io.netty.channel.ChannelPromise;

public class HttpResponseDelayHandler extends ChannelOutboundHandlerAdapter {
    @Override
    public void write(ChannelHandlerContext ctx, Object msg, final ChannelPromise promise) {

        ByteBuf buf = (ByteBuf) msg;

        int totalSize = buf.readableBytes();
        int slice1 = totalSize/2;
        int slice2 = totalSize - slice1;

        ByteBuf out = buf.readSlice(slice1).retain();
        final ByteBuf out2 = buf.readSlice(slice2).retain();

        ctx.write(out);
        
        ctx.executor().schedule(new Runnable() {
            @Override
            public void run() {
                ctx.writeAndFlush(out2, promise);
            }
        }, 3, TimeUnit.SECONDS);

        buf.release();

    }
}