用Netty实现的简单HTTP服务器

用Netty实现的一个简单的HTTP服务器，可以处理静态文件，例子中的注释也比较全。主要是对HTTP的理解，接下来的文章中我也会更新一些HTTP相关的文章以及对例子的进一步完善，由浅到深，记录一些我的

用Netty实现的一个简单的HTTP服务器，可以处理静态文件，例子中的注释也比较全。主要是对HTTP的理解，接下来的文章中我也会更新一些HTTP相关的文章以及对例子的进一步完善，由浅到深，记录一些我的学习过程！

1.Server

public class HttpServer {	public static void main(String[] args) {		ServerBootstrap bootstrap = new ServerBootstrap(new NioServerSocketChannelFactory(				Executors.newCachedThreadPool(), Executors.newCachedThreadPool()));		bootstrap.setPipelineFactory(new HttpServerPipelineFactory());		bootstrap.bind(new InetSocketAddress(8080));		System.out.println("服务器已经启动，请访问http://127.0.0.1:8080/index.html进行测试！/n/n");	}}

2.Pipeline

public class HttpServerPipelineFactory implements ChannelPipelineFactory {	public ChannelPipeline getPipeline() throws Exception {		// Create a default pipeline implementation.		ChannelPipeline pipeline = pipeline();		// Uncomment the following line if you want HTTPS		// SSLEngine engine =		// SecureChatSslContextFactory.getServerContext().createSSLEngine();		// engine.setUseClientMode(false);		// pipeline.addLast("ssl", new SslHandler(engine));		pipeline.addLast("decoder", new HttpRequestDecoder());		// Uncomment the following line if you don't want to handle HttpChunks.		// pipeline.addLast("aggregator", new HttpChunkAggregator(1048576));		pipeline.addLast("encoder", new HttpResponseEncoder());		// Remove the following line if you don't want automatic content		// compression.		//pipeline.addLast("aggregator", new HttpChunkAggregator(1048576));		pipeline.addLast("chunkedWriter", new ChunkedWriteHandler());		pipeline.addLast("deflater", new HttpContentCompressor());		pipeline.addLast("handler", new HttpRequestHandler());		return pipeline;	}}

3.handler类

import static org.jboss.netty.handler.codec.http.HttpHeaders.is100ContinueExpected;import static org.jboss.netty.handler.codec.http.HttpHeaders.isKeepAlive;import static org.jboss.netty.handler.codec.http.HttpHeaders.Names.CONTENT_LENGTH;import static org.jboss.netty.handler.codec.http.HttpHeaders.Names.COOKIE;import static org.jboss.netty.handler.codec.http.HttpHeaders.Names.SET_COOKIE;import static org.jboss.netty.handler.codec.http.HttpResponseStatus.CONTINUE;import static org.jboss.netty.handler.codec.http.HttpResponseStatus.OK;import static org.jboss.netty.handler.codec.http.HttpVersion.HTTP_1_1;import java.io.File;import java.io.RandomAccessFile;import java.util.List;import java.util.Map;import java.util.Map.Entry;import java.util.Set;import org.jboss.netty.buffer.ChannelBuffer;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.http.Cookie;import org.jboss.netty.handler.codec.http.CookieDecoder;import org.jboss.netty.handler.codec.http.CookieEncoder;import org.jboss.netty.handler.codec.http.DefaultHttpResponse;import org.jboss.netty.handler.codec.http.HttpChunk;import org.jboss.netty.handler.codec.http.HttpChunkTrailer;import org.jboss.netty.handler.codec.http.HttpHeaders;import org.jboss.netty.handler.codec.http.HttpMethod;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.handler.codec.http.QueryStringDecoder;import org.jboss.netty.handler.stream.ChunkedFile;import org.jboss.netty.util.CharsetUtil;public class HttpRequestHandler extends SimpleChannelUpstreamHandler {	private HttpRequest request;	private boolean readingChunks;	@Override	public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) throws Exception {		if (!readingChunks) {			HttpRequest request = this.request = (HttpRequest) e.getMessage();			String uri = request.getUri();			System.out.println("-----------------------------------------------------------------");			System.out.println("uri:"+uri);			System.out.println("-----------------------------------------------------------------");			/**			 * 100 Continue			 * 是这样的一种情况：HTTP客户端程序有一个实体的主体部分要发送给服务器，但希望在发送之前查看下服务器是否会			 * 接受这个实体，所以在发送实体之前先发送了一个携带100			 * Continue的Expect请求首部的请求。服务器在收到这样的请求后，应该用 100 Continue或一条错误码来进行响应。			 */			if (is100ContinueExpected(request)) {				send100Continue(e);			}			// 解析http头部			for (Map.Entry<String, String> h : request.getHeaders()) {				System.out.println("HEADER: " + h.getKey() + " = " + h.getValue() + "/r/n");			}			// 解析请求参数			QueryStringDecoder queryStringDecoder = new QueryStringDecoder(request.getUri());			Map<String, List<String>> params = queryStringDecoder.getParameters();			if (!params.isEmpty()) {				for (Entry<String, List<String>> p : params.entrySet()) {					String key = p.getKey();					List<String> vals = p.getValue();					for (String val : vals) {						System.out.println("PARAM: " + key + " = " + val + "/r/n");					}				}			}			if (request.isChunked()) {				readingChunks = true;			} else {				ChannelBuffer content = request.getContent();				if (content.readable()) {					System.out.println(content.toString(CharsetUtil.UTF_8));				}				writeResponse(e, uri);			}		} else {// 为分块编码时			HttpChunk chunk = (HttpChunk) e.getMessage();			if (chunk.isLast()) {				readingChunks = false;				// END OF CONTENT/r/n"				HttpChunkTrailer trailer = (HttpChunkTrailer) chunk;				if (!trailer.getHeaderNames().isEmpty()) {					for (String name : trailer.getHeaderNames()) {						for (String value : trailer.getHeaders(name)) {							System.out.println("TRAILING HEADER: " + name + " = " + value + "/r/n");						}					}				}				writeResponse(e, "/");			} else {				System.out.println("CHUNK: " + chunk.getContent().toString(CharsetUtil.UTF_8)						+ "/r/n");			}		}	}	private void writeResponse(MessageEvent e, String uri) {		// 解析Connection首部，判断是否为持久连接		boolean keepAlive = isKeepAlive(request);		// Build the response object.		HttpResponse response = new DefaultHttpResponse(HTTP_1_1, OK);		response.setStatus(HttpResponseStatus.OK);		// 服务端可以通过location首部将客户端导向某个资源的地址。		// response.addHeader("Location", uri);		if (keepAlive) {			// Add 'Content-Length' header only for a keep-alive connection.			response.setHeader(CONTENT_LENGTH, response.getContent().readableBytes());		}		// 得到客户端的cookie信息，并再次写到客户端		String cookieString = request.getHeader(COOKIE);		if (cookieString != null) {			CookieDecoder cookieDecoder = new CookieDecoder();			Set<Cookie> cookies = cookieDecoder.decode(cookieString);			if (!cookies.isEmpty()) {				CookieEncoder cookieEncoder = new CookieEncoder(true);				for (Cookie cookie : cookies) {					cookieEncoder.addCookie(cookie);				}				response.addHeader(SET_COOKIE, cookieEncoder.encode());			}		}		final String path = Config.getRealPath(uri);		File localFile = new File(path);		// 如果文件隐藏或者不存在		if (localFile.isHidden() || !localFile.exists()) {			// 逻辑处理			return;		}		// 如果请求路径为目录		if (localFile.isDirectory()) {			// 逻辑处理			return;		}		RandomAccessFile raf = null;		try {			raf = new RandomAccessFile(localFile, "r");			long fileLength = raf.length();			response.setHeader(HttpHeaders.Names.CONTENT_LENGTH, String.valueOf(fileLength));			Channel ch = e.getChannel();			ch.write(response);			// 这里又要重新温习下http的方法，head方法与get方法类似，但是服务器在响应中只返回首部，不会返回实体的主体部分			if (!request.getMethod().equals(HttpMethod.HEAD)) {				ch.write(new ChunkedFile(raf, 0, fileLength, 8192));//8kb			}		} catch (Exception e2) {			e2.printStackTrace();		} finally {			if (keepAlive) {				response.setHeader(CONTENT_LENGTH, response.getContent().readableBytes());			}			if (!keepAlive) {				e.getFuture().addListener(ChannelFutureListener.CLOSE);			}		}	}	private void send100Continue(MessageEvent e) {		HttpResponse response = new DefaultHttpResponse(HTTP_1_1, CONTINUE);		e.getChannel().write(response);	}	@Override	public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) throws Exception {		e.getCause().printStackTrace();		e.getChannel().close();	}}

4.配置类

public class Config {	public static String getRealPath(String uri) {		StringBuilder sb=new StringBuilder("/home/guolei/workspace/Test/web");		sb.append(uri);		if (!uri.endsWith("/")) {			sb.append('/');		}		return sb.toString();	}}

5.页面

在项目中新建一个文件夹，名称为web（可以在配置中配置），在文件夹中放入静态页面index.html。

6.启动服务器，测试