使用 Netty 编写 http服务器

import static org.jboss.netty.channel.Channels.pipeline;   
  
import java.net.InetSocketAddress;   
import java.util.concurrent.Executors;   
  
import org.jboss.netty.bootstrap.ServerBootstrap;   
import org.jboss.netty.channel.ChannelPipeline;   
import org.jboss.netty.channel.ChannelPipelineFactory;   
import org.jboss.netty.channel.Channels;   
import org.jboss.netty.channel.socket.nio.NioServerSocketChannelFactory;   
import org.jboss.netty.handler.codec.http.HttpChunkAggregator;   
import org.jboss.netty.handler.codec.http.HttpRequestDecoder;   
import org.jboss.netty.handler.codec.http.HttpResponseEncoder;   
import org.jboss.netty.handler.stream.ChunkedWriteHandler;   
  
/**  
 * 后台管理服务  
 *   
 * @author javagg  
 *   
 */  
public class AdminServer {   
    public static void main(String[] args) {   
        start(8080);   
    }   
  
    public static void start(int port) {   
        // 配置服务器-使用java线程池作为解释线程   
        ServerBootstrap bootstrap = new ServerBootstrap(new NioServerSocketChannelFactory(Executors.newCachedThreadPool(), Executors.newCachedThreadPool()));   
        // 设置 pipeline factory.   
        bootstrap.setPipelineFactory(new ServerPipelineFactory());   
        // 绑定端口   
        bootstrap.bind(new InetSocketAddress(port));   
        System.out.println(“admin start on ”+port);   
    }   
  
    private static class ServerPipelineFactory implements  
            ChannelPipelineFactory {   
        public ChannelPipeline getPipeline() throws Exception {   
            // Create a default pipeline implementation.   
            ChannelPipeline pipeline = Channels.pipeline();   
            pipeline.addLast(“decoder”, new HttpRequestDecoder());   
            pipeline.addLast(“encoder”, new HttpResponseEncoder());   
            //http处理handler   
            pipeline.addLast(“handler”, new AdminServerHandler());   
            return pipeline;   
        }   
    }   
}

import static org.jboss.netty.handler.codec.http.HttpHeaders.Names.CONTENT_TYPE;   
import static org.jboss.netty.handler.codec.http.HttpResponseStatus.BAD_REQUEST;   
import static org.jboss.netty.handler.codec.http.HttpResponseStatus.INTERNAL_SERVER_ERROR;   
import static org.jboss.netty.handler.codec.http.HttpResponseStatus.OK;   
import static org.jboss.netty.handler.codec.http.HttpVersion.HTTP_1_1;   
  
import java.util.HashMap;   
  
import org.jboss.netty.buffer.ChannelBuffers;   
import org.jboss.netty.buffer.DynamicChannelBuffer;   
import org.jboss.netty.channel.Channel;   
import org.jboss.netty.channel.ChannelFutureListener;   
import org.jboss.netty.channel.ChannelHandlerContext;   
import org.jboss.netty.channel.ExceptionEvent;   
import org.jboss.netty.channel.MessageEvent;   
import org.jboss.netty.channel.SimpleChannelUpstreamHandler;   
import org.jboss.netty.handler.codec.frame.TooLongFrameException;   
import org.jboss.netty.handler.codec.http.DefaultHttpResponse;   
import org.jboss.netty.handler.codec.http.HttpRequest;   
import org.jboss.netty.handler.codec.http.HttpResponse;   
import org.jboss.netty.handler.codec.http.HttpResponseStatus;   
import org.jboss.netty.util.CharsetUtil;   
  
/**  
 * @author javagg  
 */  
public class AdminServerHandler extends SimpleChannelUpstreamHandler {   
  
    @Override  
    public void messageReceived(ChannelHandlerContext ctx, MessageEvent e)   
            throws Exception {   
        HttpRequest request = (HttpRequest) e.getMessage();   
        String uri = request.getUri();   
                          System.out.println(“uri:”+uri);   
        HttpResponse response = new DefaultHttpResponse(HTTP_1_1, OK);   
                          ChannelBuffer buffer=new DynamicChannelBuffer(2048);   
        buffer.writeBytes(“hello, oschina”.getBytes(“UTF-8″));   
        response.setContent(buffer);   
        response.setHeader(“Content-Type”, ”text/html; charset=UTF-8″);   
        response.setHeader(“Content-Length”, response.getContent().writerIndex());   
        Channel ch = e.getChannel();   
        // Write the initial line and the header.   
        ch.write(response);   
        ch.disconnect();   
        ch.close();   
           
    }   
  
    @Override  
    public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e)   
            throws Exception {   
        Channel ch = e.getChannel();   
        Throwable cause = e.getCause();   
        if (cause instanceof TooLongFrameException) {   
            sendError(ctx, BAD_REQUEST);   
            return;   
        }   
  
        cause.printStackTrace();   
        if (ch.isConnected()) {   
            sendError(ctx, INTERNAL_SERVER_ERROR);   
        }   
    }   
  
    private void sendError(ChannelHandlerContext ctx, HttpResponseStatus status) {   
        HttpResponse response = new DefaultHttpResponse(HTTP_1_1, status);   
        response.setHeader(CONTENT_TYPE, ”text/plain; charset=UTF-8″);   
        response.setContent(ChannelBuffers.copiedBuffer(“Failure: ” + status.toString() + ”\r\n”, CharsetUtil.UTF_8));   
  
        // Close the connection as soon as the error message is sent.   
        ctx.getChannel().write(response).addListener(ChannelFutureListener.CLOSE);   
    }   
}