近来有空,研究了一下netty。netty5还仅仅是beta版本号。官方建议使用netty4。
这个实例中,Client通过控制台输入信息,与Server端通信。
对于普通开发人员来说,netty4的经常使用接口有:SimpleChannelInboundHandler/SimpleChannelOutboundHandler、ChannelInitializer、encoder和decoder相关的类。
server端:
1、编写handler类
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
public class ServerHandler extends SimpleChannelInboundHandler {
@Override
public void channelRead0(ChannelHandlerContext ctx, Object msg) throws Exception {
System.out.println("server:" + "channelRead:" + msg);
ctx.writeAndFlush("Received your message !");
}
}
2、注冊服务。绑定port:
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.protobuf.ProtobufDecoder;
import io.netty.handler.codec.protobuf.ProtobufEncoder;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.codec.string.StringEncoder;
public class Server {
public static void main(String[] args) {
EventLoopGroup bossEventLoopGroup = new NioEventLoopGroup();
EventLoopGroup workerEventLoopGroup = new NioEventLoopGroup();
try {
ServerBootstrap serverBootstrap = new ServerBootstrap();
serverBootstrap.group(bossEventLoopGroup, workerEventLoopGroup);
serverBootstrap.channel(NioServerSocketChannel.class);
serverBootstrap.childHandler(new ChannelInitializer<Channel>() {
@Override
protected void initChannel(Channel ch) throws Exception {
ch.pipeline().addLast("encoder", new StringEncoder());
ch.pipeline().addLast("decoder", new StringDecoder());
ch.pipeline().addLast("handler", new ServerHandler());
};
});
serverBootstrap.childOption(ChannelOption.SO_KEEPALIVE, true);
ChannelFuture channelFuture = serverBootstrap.bind(8888).sync();
channelFuture.channel().closeFuture().sync();
} catch (Exception e) {
e.printStackTrace();
} finally {
bossEventLoopGroup.shutdownGracefully();
workerEventLoopGroup.shutdownGracefully();
}
}
}
client:
1、编写handler类
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
public class ClientHandler extends SimpleChannelInboundHandler {
@Override
protected void channelRead0(ChannelHandlerContext ctx, Object msg) throws Exception {
System.out.println("client:" + "channelRead:" + msg);
}
}
2、编写请求入口
import java.io.BufferedReader;
import java.io.InputStreamReader;
import io.netty.bootstrap.Bootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.protobuf.ProtobufDecoder;
import io.netty.handler.codec.protobuf.ProtobufEncoder;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.codec.string.StringEncoder;
public class Client {
public static void main(String[] args) {
EventLoopGroup eventLoopGroup = new NioEventLoopGroup();
try {
Bootstrap bootstrap = new Bootstrap();
bootstrap.group(eventLoopGroup);
bootstrap.channel(NioSocketChannel.class);
bootstrap.handler(new ChannelInitializer<Channel>() {
@Override
protected void initChannel(Channel ch) throws Exception {
ch.pipeline().addLast("encoder", new StringEncoder());
ch.pipeline().addLast("decoder", new StringDecoder());
ch.pipeline().addLast("handler", new ClientHandler());
};
});
Channel ch = bootstrap.connect("127.0.0.1", 8888).sync().channel();
// 控制台输入
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
for (;;) {
String line = in.readLine();
if (line == null || "".equals(line)) {
continue;
}
ch.writeAndFlush(line);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
eventLoopGroup.shutdownGracefully();
}
}
}
新手教程,欢迎拍砖~