Netty入门之发送序列化对象

Netty发送序列化对象主要在于两个Handler：

ObjectEncoder：对象编码器，将输出Serializable对象编码为字节对象ByteBuf，用于写出对象

ObjectDecoder：对象解码器，将输入的ByteBuf字节对象解码为Serializable对象，用于读入对象

 

ObjectEchoClient

import io.netty.bootstrap.Bootstrap;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.serialization.ClassResolvers;
import io.netty.handler.codec.serialization.ObjectDecoder;
import io.netty.handler.codec.serialization.ObjectEncoder;
import io.netty.handler.ssl.SslContext;
import io.netty.handler.ssl.SslContextBuilder;
import io.netty.handler.ssl.util.InsecureTrustManagerFactory;
import lombok.extern.slf4j.Slf4j;

/**
 * Java序列化对象客户端
 */
@Slf4j
public final class ObjectEchoClient {

    static final boolean SSL = System.getProperty("ssl") != null;
    static final String HOST = System.getProperty("host", "127.0.0.1");
    static final int PORT = Integer.parseInt(System.getProperty("port", "8080"));
    static final int SIZE = Integer.parseInt(System.getProperty("size", "15"));

    public static void main(String[] args) throws Exception {

        final SslContext sslCtx;
        if (SSL) {
            sslCtx = SslContextBuilder.forClient().trustManager(InsecureTrustManagerFactory.INSTANCE).build();
        } else {
            sslCtx = null;
        }

        EventLoopGroup group = new NioEventLoopGroup();
        try {
            Bootstrap b = new Bootstrap();
            b.group(group)
                    .channel(NioSocketChannel.class)
                    .handler(new ChannelInitializer<SocketChannel>() {
                        @Override
                        public void initChannel(SocketChannel ch) throws Exception {
                            ChannelPipeline p = ch.pipeline();
                            if (sslCtx != null) {
                                p.addLast(sslCtx.newHandler(ch.alloc(), HOST, PORT));
                            }
                            p.addLast(
                                    new ObjectEncoder(),//序列化对象编码器
                                    new ObjectDecoder(ClassResolvers.cacheDisabled(null)),//序列化对象解码器
                                    new ObjectEchoClientHandler());
                        }
                    });
            log.info("客户端启动");
            b.connect(HOST, PORT).sync().channel().closeFuture().sync();
        } finally {
            group.shutdownGracefully();
        }
    }
}

1.在业务Handler之前设置了ObjectEncoder和ObjectDecoder

2.对象解码Handler可以设置类解析器

 

ObjectEchoClientHandler

import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import lombok.extern.slf4j.Slf4j;

import java.util.ArrayList;
import java.util.List;

/**
 * 对象回显客户端的处理程序实现。它通过将第一条消息发送到服务器，从而在对象回显客户端和服务器之间启动*乒乓通信。
 */
@Slf4j
public class ObjectEchoClientHandler extends ChannelInboundHandlerAdapter {

    private final List<Integer> firstMessage;

    public ObjectEchoClientHandler() {
        /* 初始化对象，ArrayList为序列化对象 */
        firstMessage = new ArrayList<Integer>(ObjectEchoClient.SIZE);
        for (int i = 0; i < ObjectEchoClient.SIZE; i ++) {
            firstMessage.add(Integer.valueOf(i));
        }
    }

    @Override
    public void channelActive(ChannelHandlerContext ctx) {
        ctx.writeAndFlush(firstMessage);
    }

    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg)throws Exception {
        log.info("客户端收到信息："+msg.toString());
        Thread.sleep(2000L);
        /* 乒乓通信 */
        ctx.write(msg);
    }

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) {
        ctx.flush();
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
        cause.printStackTrace();
        ctx.close();
    }
}

1.继承的类没有泛型，这里使用的还是Object对象

2.实现的读取方法为channelRead，也是使用Object为对象

3.服务端也是一样