Netty使用实例
贴上两个自己写好的Netty使用实例，以便备注，以下两个例子基于netty-3.5.7.Final.jar用Junit进行测试
Netty 的详细介绍：请点这里
Netty 的下载地址：请点这里
第一个例子：简单的发送字符串，接收字符串“Hello, World”
package com.wujintao.netty;
import java.net.InetSocketAddress;
import java.util.concurrent.Executors;
import org.jboss.netty.bootstrap.ClientBootstrap;
import org.jboss.netty.bootstrap.ServerBootstrap;
import org.jboss.netty.channel.ChannelFuture;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.channel.ChannelPipeline;
import org.jboss.netty.channel.ChannelPipelineFactory;
import org.jboss.netty.channel.ChannelStateEvent;
import org.jboss.netty.channel.Channels;
import org.jboss.netty.channel.ExceptionEvent;
import org.jboss.netty.channel.MessageEvent;
import org.jboss.netty.channel.SimpleChannelHandler;
import org.jboss.netty.channel.socket.nio.NioClientSocketChannelFactory;
import org.jboss.netty.channel.socket.nio.NioServerSocketChannelFactory;
import org.jboss.netty.handler.codec.string.StringDecoder;
import org.jboss.netty.handler.codec.string.StringEncoder;
import org.junit.Test;
class HelloWorldServerHandler extends SimpleChannelHandler {
public void channelConnected(ChannelHandlerContext ctx, ChannelStateEvent e)
throws Exception {
e.getChannel().write("Hello, World");
}
public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) {
System.out.println("Unexpected exception from downstream."
+ e.getCause());
e.getChannel().close();
}
}
class HelloWorldClientHandler extends SimpleChannelHandler {
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
String message = (String) e.getMessage();
System.out.println(message);
e.getChannel().close();
}
public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) {
System.out.println("Unexpected exception from downstream."
+ e.getCause());
e.getChannel().close();
}
}
/**
* Netty VS MinaNetty基于Pipeline处理，Mina基于Filter过滤
* Netty的事件驱动模型具有更好的扩展性和易用性
* Https，SSL，PB，RSTP，Text &Binary等协议支持
* Netty中UDP传输有更好的支持官方测试Netty比Mina性能更好
* @author Administrator
*
*/
public class TestCase {
public void testServer() {
//初始化channel的辅助类，为具体子类提供公共数据结构
ServerBootstrap bootstrap = new ServerBootstrap(
new NioServerSocketChannelFactory(
Executors.newCachedThreadPool(),
Executors.newCachedThreadPool()));
bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
public ChannelPipeline getPipeline() {
ChannelPipeline pipeline = Channels.pipeline();
pipeline.addLast("decoder", new StringDecoder());
pipeline.addLast("encoder", new StringEncoder());
pipeline.addLast("handler", new HelloWorldServerHandler());
return pipeline;
}
});
//创建服务器端channel的辅助类,接收connection请求
bootstrap.bind(new InetSocketAddress(8080));
}
public void testClient() {
//创建客户端channel的辅助类,发起connection请求
ClientBootstrap bootstrap = new ClientBootstrap(
new NioClientSocketChannelFactory(
Executors.newCachedThreadPool(),
Executors.newCachedThreadPool()));
//It means one same HelloWorldClientHandler instance is going to handle multiple Channels and consequently the data will be corrupted.
//基于上面这个描述，必须用到ChannelPipelineFactory每次创建一个pipeline
bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
public ChannelPipeline getPipeline() {
ChannelPipeline pipeline = Channels.pipeline();
pipeline.addLast("decoder", new StringDecoder());
pipeline.addLast("encoder", new StringEncoder());
pipeline.addLast("handler", new HelloWorldClientHandler());
return pipeline;
}
});
//创建无连接传输channel的辅助类(UDP),包括client和server
ChannelFuture future = bootstrap.connect(new InetSocketAddress(
"localhost", 8080));
future.getChannel().getCloseFuture().awaitUninterruptibly();
bootstrap.releaseExternalResources();
}
@Test
public void testNetty(){
testServer();
testClient();
}
}