一、初始化 ChannelPipeline

我们之前说过为了将 ChannelHandler 安装到 ChannelPipeline 中，需要扩展了ChannelInitializer，并实现 initChannel()方法。

下面我们演示一下：

import io.netty.channel.Channel;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.group.ChannelGroup;
import io.netty.handler.codec.http.HttpObjectAggregator;
import io.netty.handler.codec.http.HttpServerCodec;
import io.netty.handler.codec.http.websocketx.WebSocketServerProtocolHandler;
import io.netty.handler.stream.ChunkedWriteHandler;

/**
 * Author: lhd
 * Data: 2023/6/12
 * Annotate: 初始化 ChannelPipeline
 */
public class ChatServerInitializer extends ChannelInitializer<Channel> {
   
    private final ChannelGroup group;
    public ChatServerInitializer(ChannelGroup group) {
   
        this.group = group;
    }
    @Override
    protected void initChannel(Channel ch) throws Exception {
    
        ChannelPipeline pipeline = ch.pipeline();
        //将所有需要的ChannelHandler 添加到 ChannelPipeline 中
        pipeline.addLast(new HttpServerCodec());
        pipeline.addLast(new ChunkedWriteHandler());
        pipeline.addLast(new HttpObjectAggregator(64 * 1024));
        pipeline.addLast(new HttpRequestHandler("/ws"));
        pipeline.addLast(new WebSocketServerProtocolHandler("/ws"));
        pipeline.addLast(new TextWebSocketFrameHandler(group))