Grizzly开发Echo服务器实战

Grizzly开发Echo服务器实战

用Java编写可伸缩的服务器应用是有难度的，用Java NIO开发、线程管理、为成千上万的用户做服务器扩展，这些都是难点。Grizzly NIO框架的设计目标就是帮助开发者很好地利用Java NIO API，编写出高可扩展性的、功能强大的服务器，并提高了扩展的框架组件：Web Framework（HTTP/S）、WebSocket、Comet等。

Grizzly 2.3开发Echo服务器/客户端的例子

1、下载grizzly-framework.jar库

Maven依赖

org.glassfish.grizzlygrizzly-framework2.3.16

import java.io.IOException;

import org.glassfish.grizzly.filterchain.BaseFilter;
import org.glassfish.grizzly.filterchain.FilterChainContext;
import org.glassfish.grizzly.filterchain.NextAction;


public class EchoFilter extends BaseFilter{
	
	/**
	 * 仅处理读操作，当消息到来时进行处理
	 * @param ctx  处理的上下文
	 * @return 下一个动作
	 */
	@Override
	public NextAction handleRead(FilterChainContext ctx) throws IOException{
		// Peer address用于无连接的UDP连接
		final Object peerAddress = ctx.getAddress();
		final Object message = ctx.getMessage();
		System.out.println("Server received: " + message);
		ctx.write(peerAddress, message, null);
		return ctx.getStopAction();
	}
}

import java.io.IOException;
import java.nio.charset.Charset;
import java.util.logging.Logger;


import org.glassfish.grizzly.filterchain.FilterChainBuilder;
import org.glassfish.grizzly.filterchain.TransportFilter;
import org.glassfish.grizzly.nio.transport.TCPNIOTransport;
import org.glassfish.grizzly.nio.transport.TCPNIOTransportBuilder;
import org.glassfish.grizzly.utils.StringFilter;


public class EchoServer {
	private static final Logger logger = Logger.getLogger(EchoServer.class.getName());
	public static final String HOST = "localhost";
	public static final int PORT = 7777;
	
	public static void main(String[] args) throws IOException{
		// 用FilterChainBuilder创建过滤器链
		FilterChainBuilder filterChainBuilder = FilterChainBuilder.stateless();
		
		// 添加TransportFilter，它负责从连接中读数据，并写数据到连接
		filterChainBuilder.add(new TransportFilter());
		// 字符串过滤器StringFilter负责缓冲和字符串之间的转换
		filterChainBuilder.add(new StringFilter(Charset.forName("UTF-8")));
		// 过滤器EchoFilter负责把接收到的消息原样返回给连接
		filterChainBuilder.add(new EchoFilter());
		
		// 创建TCP传输
		final TCPNIOTransport transport = TCPNIOTransportBuilder.newInstance().build();
		transport.setProcessor(filterChainBuilder.build());
		try{
			// 绑定传输，开始对主机+端口进行监听
			transport.bind(HOST, PORT);
			// 开始传输
			transport.start();
			
			logger.info("Press any key to stop the Echo server...");
			System.in.read();
		} finally{
			logger.info("Stopping transport...");
			// 停止传输服务器
			transport.shutdown();
			
			logger.info("Stopped transport...");
		}
	}
}

java -classpath grizzly-framework.jar EchoServer

import java.io.IOException;


import org.glassfish.grizzly.filterchain.BaseFilter;
import org.glassfish.grizzly.filterchain.FilterChainContext;
import org.glassfish.grizzly.filterchain.NextAction;


public class ClientFilter extends BaseFilter{
	
	/**
	 * 仅处理读操作，当消息到来时进行处理
	 * @param ctx  处理的上下文
	 * @return 下一个动作
	 */
	@Override
	public NextAction handleRead(final FilterChainContext ctx) throws IOException{
		// 从上下文得到字符串消息，过滤器链只使用了字符串过滤器StringFilter
		final String serverResponse = ctx.getMessage();
		System.out.println("Server echo: " + serverResponse);
		return ctx.getStopAction();
	}
}

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.nio.charset.Charset;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.logging.Logger;


import org.glassfish.grizzly.Connection;
import org.glassfish.grizzly.Grizzly;
import org.glassfish.grizzly.filterchain.FilterChainBuilder;
import org.glassfish.grizzly.filterchain.TransportFilter;
import org.glassfish.grizzly.nio.transport.TCPNIOTransport;
import org.glassfish.grizzly.nio.transport.TCPNIOTransportBuilder;
import org.glassfish.grizzly.utils.StringFilter;


import ch.echo.server.EchoServer;


public class EchoClient {
	private static final Logger logger = Grizzly.logger(EchoClient.class);
	
	public static void main(String[] args) throws IOException,
		ExecutionException, InterruptedException, TimeoutException{
		Connection connection = null;
		
		// 用FilterChainBuilder类创建过滤器链
		FilterChainBuilder filterChainBuilder = FilterChainBuilder.stateless();
		// 添加传输过滤器，它负责从连接读数据并向连接写数据
		filterChainBuilder.add(new TransportFilter());
		// 添加字符串过滤器，它负责缓冲和字符串之间的转换
		filterChainBuilder.add(new StringFilter(Charset.forName("UTF-8")));
		// 添加客户端过滤器，他负责把服务器响应重定向到标准输出
		filterChainBuilder.add(new ClientFilter());
		
		// 创建TCP传输
		final TCPNIOTransport transport = TCPNIOTransportBuilder.newInstance().build();
		transport.setProcessor(filterChainBuilder.build());
		
		try{
			// 启动传输
			transport.start();
			
			// 异步执行，连接到服务器
			Future future = transport.connect(EchoServer.HOST, EchoServer.PORT);
			// 等待连接操作的完成
			connection = future.get(10, TimeUnit.SECONDS);
			
			assert connection!=null;
			System.out.println("Ready...(\"q\" to exit");
			final BufferedReader inReader = new BufferedReader(new InputStreamReader(System.in));
			do{
				final String userInput = inReader.readLine();
				if(userInput==null || "q".equals(userInput))
					break;
				
				connection.write(userInput);
			} while(true);
		} finally{
			// 关闭客户端连接
			if(connection!=null)
				connection.close();
			
			// 停止传输
			transport.shutdownNow();
		}
	}
}

java -classpath grizzly-framework.jar EchoClient