基于AIO的超轻量HTTP服务器实现

高端大气上档次的网页PPT：

1.很多人写了多年代码，从未接触过

2.很多人做了多年Web，从未了解过HTTP协议

3.很多人看过HTML5规范，从未使用过

Java Aio , JDK1.7之后新出的一个重量级API，可以看作是JDK1.4 NIO 之后的一次升级，但相比NIO 的模型，AIO的模型优势在于当操作系统内核处于可读或则可写状态的时候，操作系统会主动通知应用程序，所以AIO使用起来比NIO就简单很多。

HTTP 协议，如果问起来，很多人一致的回答都是基于TCP的文本传输协议，但是真正了解它如何工作的人少之有少，什么是包头，什么是包体，分割符号是什么，程序如何才能够有条不紊地处理，什么是Keep-Alive，什么是长轮询，的内部原理是什么。或许很多人看过相关书籍，但却止步于书籍，、Netty、Jetty的源码又相当复杂，难于记忆。TCP协议、HTTP协议的一时半会儿说不清，所以就跟随我一步一步实现一个轻量的http-aio-，相信大家很快就能够明白它们原理。

的目标1：实现常用的GET/POST请求方法，GET方法支持URL参数，POST方法支持/x-www-form-、/form-data和流式上传,再就是全双工协议封装。

的目标2：基于的开发，并且实现类似 MVC的开发。

源代码已上传，详细请见Maven项目源码，test目录的可以直接启动

下面是精简后的源码，简单过目后便可大致了解AIO处理流程

/*** @author fangjialong* @description 服务器启动类，主要作用是创建线程池，绑定端口，开始接受Socket请求，该代码是精简后的代码，详细请下载源码*/
public class HttpServer {private ExecutorService channelWorkers;private ExecutorService processWorkers;private AsynchronousChannelGroup workerGroup = null;private AsynchronousServerSocketChannel serverSocket = null;private SocketAcceptHandler socketAcceptHandler;public synchronized void startup() throws IOException {//根据硬件环境创建线程池int availableProcessors = Runtime.getRuntime().availableProcessors();channelWorkers = Executors.newFixedThreadPool(availableProcessors+1,new ProcessorThreadFactory());workerGroup = AsynchronousChannelGroup.withCachedThreadPool(channelWorkers, 1);serverSocket = AsynchronousServerSocketChannel.open(workerGroup);//绑定服务器端口serverSocket.bind(new InetSocketAddress(80), 100);//开始接收请求，并且传入异步回调serverSocket.accept(null, socketAcceptHandler);}
}

下面是接受到请求后创建套接字会话，创建会话是为了方便编解码，和等待接受下次HTTP请求。

/*** @author cannonfang* @name 房佳龙* @date 2014-1-9* @qq 271398203* @todo 该类用于接受客户端TCP连接，如果有一个新的TCP连接，该类的completed函数将会被调用*/
@Component
public class SocketAcceptHandler implements CompletionHandler{private static final Logger logger = LoggerFactory.getLogger(SocketAcceptHandler.class);private HttpServer server;public void setServer(HttpServer server) {this.server = server;}@Overridepublic void completed(AsynchronousSocketChannel socket,Object obj) {try{SocketSession session = new SocketSession(socket,server);
//			logger.debug("Socket Session({}) Create",session.hashCode());session.read();}catch(Throwable t){logger.error(t.getMessage(),t);try {socket.close();} catch (IOException e) {}}finally{server.accept();}}@Overridepublic void failed(Throwable t, Object obj) {server.accept();}}

HTTP 编码和解码对象，HTTP请求的解析总共分为三部，读取第一行，通过该行可以判断HTTP请求方法，版本和请求URI，每行以回车（ASCII:13）换行（ASCII:10）分割；然后读取HTTP , 每行以分好(:)和一个空白符作为分割组成Key-Value，已两个回车换行作为头部读取完毕；最后判断HTTP 中是否存在-头，如果存在，则通过Value中的数字作为长度继续向后读取作为包体，如果-: 1024， 那么就应该继续读取1024个字节作为包体。下面的代码部分来至Netty源码，相信阅读过Netty源码的同学会再这发现曾经的影子。

/*** @author cannonfang* @name 房佳龙* @date 2014-1-13* @qq 271398203* @todo HTTP Response Encode And Decode Class*/
@Component
public class HttpMessageSerializer implements InitializingBean{protected Logger logger = LoggerFactory.getLogger(HttpMessageSerializer.class);private int maxInitialLineLength = 1024*2; //Default 2KBprivate int maxHeaderSize = 1024*4; //Default 4KBprivate int maxContextSize = 1024*1024*5 ;//Default 5MBprivate String charset = "UTF-8";private String dynamicSuffix;private String defaultIndex;private ServerConfig serverConfig;@Autowiredpublic void setServerConfig(ServerConfig serverConfig) {this.serverConfig = serverConfig;}@Overridepublic void afterPropertiesSet() throws Exception {this.charset = serverConfig.getString("server.http.charset", charset);logger.info("server.http.charset : {}",charset);this.maxHeaderSize = serverConfig.getBytesLength("server.http.maxHeaderSize", this.maxHeaderSize);logger.info("server.http.maxHeaderSize : {}",maxHeaderSize);this.maxContextSize = serverConfig.getBytesLength("server.http.maxContextSize", this.maxContextSize);logger.info("server.http.maxContextSize : {}",maxContextSize);this.dynamicSuffix = serverConfig.getString("server.http.dynamic.suffix", ".do");logger.info("server.http.dynamic.suffix : {}",dynamicSuffix);this.defaultIndex = serverConfig.getString("server.http.index", ".html");logger.info("server.http.dynamic.suffix : {}",this.defaultIndex);}public boolean decode(ByteBuffer buffer,HttpProcessor processor)throws Exception{boolean finished = false;DefaultHttpRequest request = null;try{buffer.flip();HttpSocketStatus status = processor.getSocketStatus();request = processor.getRequest();switch(status){case SKIP_CONTROL_CHARS: {skipControlCharacters(buffer);processor.setSocketStatus(HttpSocketStatus.READ_INITIAL);}case READ_INITIAL:{String line = readLine(buffer,maxInitialLineLength);if(line==null){break;}String[] initialLine = splitInitialLine(line);String text = initialLine[0].toUpperCase();HttpMethod method = HttpMethod.getHttpMethod(text);if(method==null){throw new HttpException(HttpResponseStatus.METHOD_NOT_ALLOWED, "Unsuported HTTP Method "+text);}String uri = initialLine[1];text = initialLine[2].toUpperCase();HttpVersion version;if (text.equals("HTTP/1.1")) {version=HttpVersion.HTTP_1_1;}else if (text.equals("HTTP/1.0")) {version=HttpVersion.HTTP_1_0;}else{throw new HttpException(HttpResponseStatus.BAD_REQUEST,"Unsuported HTTP Protocol "+text);}request = new DefaultHttpRequest(version,method,uri);request.setCharacterEncoding(charset);int at = uri.indexOf('?');String queryString ;if(at>=0){queryString = uri.substring(0, at);}else{queryString = uri;}if(queryString.endsWith("/")){queryString = queryString+this.defaultIndex;request.setQueryString(queryString);}else{request.setQueryString(queryString);}if(queryString.endsWith(this.dynamicSuffix)){request.setDynamic(true);if(at>0){String params = uri.substring(at);request.decodeContentAsURL(params,charset);}}else{request.setDynamic(false);}
//				logger.debug("Socket Session({}) : {}",processor.hashCode(),queryString);processor.setRequest(request);processor.setSocketStatus(HttpSocketStatus.READ_HEADER);}case READ_HEADER:{if(!readHeaders(buffer,request)){break;}long contentLength = HttpHeaders.getContentLength(request, -1);if(request.isDynamic()){if(contentLength>0){if(contentLength>this.maxContextSize){throw new HttpException(HttpResponseStatus.REQUEST_ENTITY_TOO_LARGE, "Request Entity Too Large : "+contentLength);}try {request.createContentBuffer((int)contentLength,request.getHeader(HttpHeaders.Names.CONTENT_TYPE));} catch (IOException e) {logger.info(e.getMessage(),e);throw new HttpException(HttpResponseStatus.INTERNAL_SERVER_ERROR, e.getMessage());}processor.setSocketStatus(HttpSocketStatus.READ_VARIABLE_LENGTH_CONTENT);}else{processor.setSocketStatus(HttpSocketStatus.RUNNING);finished=true;break;}}else{if(contentLength>0){throw new HttpException(HttpResponseStatus.BAD_REQUEST,"Http Static Request Do Not Suport Content Length : " + contentLength);}else{processor.setSocketStatus(HttpSocketStatus.RUNNING);finished=true;break;}}}case READ_VARIABLE_LENGTH_CONTENT:{try {if(request.readContentBuffer(buffer)){processor.setSocketStatus(HttpSocketStatus.RUNNING);finished=true;}} catch (IOException e) {logger.info(e.getMessage(),e);throw new HttpException(HttpResponseStatus.INTERNAL_SERVER_ERROR, e.getMessage());}break;}default:throw new HttpException(HttpResponseStatus.BAD_REQUEST,"Error Scoket Status : " + status);}}catch(Exception e){if(request!=null){request.destroy();}throw e;}finally{if(buffer!=null){buffer.compact();}}return finished;}public void encodeInitialLine(ByteBuffer buffer,HttpResponse response) throws IOException{byte[] bytes = response.getProtocolVersion().toString().getBytes(charset);buffer.put(bytes);buffer.put(HttpCodecUtil.SP);buffer.put(response.getStatus().getBytes());buffer.put(HttpCodecUtil.CRLF);}public void encodeHeaders(ByteBuffer buffer,HttpResponse response,SocketSession session) throws IOException, InterruptedException, ExecutionException {int remaining = buffer.remaining();for(Entry header : response.getHeaders()){byte[] key = header.getKey().getBytes(charset);byte[] value = header.getValue().getBytes(charset);remaining-=key.length+value.length+3;if(remaining<=0){buffer.flip();session.write(buffer).get();remaining = buffer.remaining();buffer.compact();}buffer.put(key);buffer.put(HttpCodecUtil.COLON_SP);buffer.put(value);buffer.put(HttpCodecUtil.CRLF);}if(remaining<=0){session.write(buffer).get();}buffer.put(HttpCodecUtil.CRLF);}public String getCharset() {return charset;}private boolean readHeaders(ByteBuffer buffer,HttpRequest request) throws HttpException {StringBuilder sb = new StringBuilder(64);int limit = buffer.limit();int position = buffer.position();int lineLength = 0;for(int index=position;index= maxHeaderSize) {throw new HttpException(HttpResponseStatus.BAD_REQUEST,"An HTTP header is larger than " + maxHeaderSize +" bytes.");}lineLength ++;sb.append((char) nextByte);}}return false;}private static void readHeader(HttpRequest request,String header){String[] kv = splitHeader(header);request.addHeader(kv[0], kv[1]);}private static String[] splitHeader(String sb) {final int length = sb.length();int nameStart;int nameEnd;int colonEnd;int valueStart;int valueEnd;nameStart = findNonWhitespace(sb, 0);for (nameEnd = nameStart; nameEnd < length; nameEnd ++) {char ch = sb.charAt(nameEnd);if (ch == ':' || Character.isWhitespace(ch)) {break;}}for (colonEnd = nameEnd; colonEnd < length; colonEnd ++) {if (sb.charAt(colonEnd) == ':') {colonEnd ++;break;}}valueStart = findNonWhitespace(sb, colonEnd);if (valueStart == length) {return new String[] {sb.substring(nameStart, nameEnd),""};}valueEnd = findEndOfString(sb);return new String[] {sb.substring(nameStart, nameEnd),sb.substring(valueStart, valueEnd)};}private static String readLine(ByteBuffer buffer, int maxLineLength) throws HttpException {StringBuilder sb = new StringBuilder(64);int lineLength = 0;int limit = buffer.limit();int position = buffer.position();for(int index=position;index= maxLineLength) {throw new HttpException(HttpResponseStatus.REQUEST_URI_TOO_LONG,"An HTTP line is larger than " + maxLineLength +" bytes.");}lineLength ++;sb.append((char) nextByte);}}return null;}private static String[] splitInitialLine(String sb) {int aStart;int aEnd;int bStart;int bEnd;int cStart;int cEnd;aStart = findNonWhitespace(sb, 0);aEnd = findWhitespace(sb, aStart);bStart = findNonWhitespace(sb, aEnd);bEnd = findWhitespace(sb, bStart);cStart = findNonWhitespace(sb, bEnd);cEnd = findEndOfString(sb);return new String[] {sb.substring(aStart, aEnd),sb.substring(bStart, bEnd),cStart < cEnd? sb.substring(cStart, cEnd) : "" };}private static int findNonWhitespace(String sb, int offset) {int result;for (result = offset; result < sb.length(); result ++) {if (!Character.isWhitespace(sb.charAt(result))) {break;}}return result;}private static int findWhitespace(String sb, int offset) {int result;for (result = offset; result < sb.length(); result ++) {if (Character.isWhitespace(sb.charAt(result))) {break;}}return result;}private static int findEndOfString(String sb) {int result;for (result = sb.length(); result > 0; result --) {if (!Character.isWhitespace(sb.charAt(result - 1))) {break;}}return result;}private static void skipControlCharacters(ByteBuffer buffer) {int limit = buffer.limit();int position = buffer.position();for(int index=position;index

public final class MethodHandler {private static final Logger logger = LoggerFactory.getLogger(MethodHandler.class);private final Object object;private final Method method;private final boolean responseBody;private final boolean xssFilter;private RequestParamType[] requestParamTypes;private int parameterLength;private ObjectMapper objectMapper;private boolean matcherHandler = false;private Pattern pattern;private String[] keys;public MethodHandler(Object object,Method method){this.object = object;this.method = method;this.responseBody=method.isAnnotationPresent(ResponseBody.class);XssFilter filter = method.getAnnotation(XssFilter.class);this.xssFilter = filter==null?true:filter.value();}public Pattern getPattern() {return pattern;}public String[] getKeys() {return keys;}public boolean isMatcherHandler() {return matcherHandler;}void setPathPattern(Pattern pattern,String[] keys) {this.pattern = pattern;this.matcherHandler = true;this.keys = keys;}void setObjectMapper(ObjectMapper objectMapper) {this.objectMapper = objectMapper;}public Method getMethod() {return method;}public Object getObject() {return object;}void setParameterTypes(Class clazz,Method method) {Class[] parameterTypes = method.getParameterTypes();Annotation[][] parameterAnnotations = method.getParameterAnnotations();this.parameterLength = parameterTypes.length;this.requestParamTypes = new RequestParamType[this.parameterLength];for(int i=0;i classType = parameterTypes[i];RequestParamType paramType = new RequestParamType();Type type;if(classType==HttpRequest.class){type = Type.HTTP_REQUEST;}else if(classType==HttpResponse.class){type = Type.HTTP_RESPONSE;}else{if(classType==String.class){type = Type.STRING;}else if(classType.isAssignableFrom(List.class)){type = Type.LIST;}else if(classType.isAssignableFrom(Set.class)){type = Type.SET;}else if(classType.isAssignableFrom(Map.class)){type = Type.MAP;}else if(classType.isArray()){type = Type.ARRARY;}else if(classType==Boolean.class||classType==boolean.class){type = Type.BOOLEAN;}else if(classType==Short.class||classType==short.class){type = Type.SHORT;}else if(classType==Integer.class||classType==int.class){type = Type.INTEGER;}else if(classType==Long.class||classType==long.class){type = Type.LONG;}else if(classType==Float.class||classType==float.class){type = Type.FLOAT;}else if(classType==Double.class||classType==double.class){type = Type.DOUBLE;}else if(classType==Character.class||classType==char.class){type = Type.CHAR;}else if(classType==Byte.class||classType==byte.class){type = Type.BYTE;}else{throw new RuntimeException(clazz.getSimpleName()+"."+method.getName()+" param["+i+"] is not suported to request params ioc");}Annotation[] annotations = parameterAnnotations[i];RequestParam requestParam = null;PathVariable pathVariable = null;for(Annotation annotation:annotations){if(annotation instanceof RequestParam){requestParam = (RequestParam)annotation;paramType.setName(requestParam.value());if(!requestParam.defaultValue().equals(ValueConstants.DEFAULT_NONE)){paramType.setDefaultValue(requestParam.defaultValue());paramType.setRequired(false);}else{paramType.setRequired(requestParam.required());}}else if(annotation instanceof PathVariable){pathVariable = (PathVariable)annotation;paramType.setName(pathVariable.value());paramType.setRequired(true);}}if(requestParam==null&& pathVariable == null){throw new RuntimeException(clazz.getSimpleName()+"."+method.getName()+" param["+i+"] must be annotation present RequestParam or PathVariable");}}paramType.setType(type);this.requestParamTypes[i] = paramType;}}public Object invoke(HttpRequest request,HttpResponse response) throws Throwable{try{if(this.parameterLength>0){Object[] params = new Object[this.parameterLength];for(int i=0;i

@Controller
public class TestController {protected Logger logger = LoggerFactory.getLogger(TestController.class);@RequestMapping("/test1.do")@ResponseBodypublic Object test1(){Map result = new HashMap();result.put("msg", "Hello World!");return result;}@RequestMapping("/test2.do")@ResponseBodypublic Object test2(@RequestParam(required=true,value="id")String id,@RequestParam(value="name",defaultValue="Unknown")String name){Map result = new HashMap();result.put("id", id);result.put("name", name);return result;}@RequestMapping("/multipart.do")public String multipart(HttpRequest request) throws Exception{FileItem file = request.getFile("file");logger.info(file.getFieldName()+":"+file.getFieldName()+":"+file.getSize());FileUtils.writeByteArrayToFile(new File("D://test.jpg"), file.get());return "success";}@RequestMapping("/xssFilter1.do")@ResponseBodypublic Object xssFilter1(HttpRequest request,HttpResponse response){return request.getParametersMap();}@RequestMapping("/xssFilter2.do")@ResponseBody@XssFilter(false)public Object xssFilter2(HttpRequest request,HttpResponse response){return request.getParametersMap();}@RequestMapping("/test/test/*")@ResponseBodypublic Object test10(){Map result = new HashMap();result.put("msg", "Hello World!");return result;}@RequestMapping("/test/{id}/index.do")@ResponseBodypublic Object test11(@PathVariable("id")String id){Map result = new HashMap();result.put("msg", "Hello World!");return result;}
}

for(;index

public class ChartSession extends SimpleWebSocket implements WebSocketSession{private Map sessions;private String name;public ChartSession(String name ,Map sessions) {super(65535);this.sessions = sessions;this.name = name;}private static final Logger logger = LoggerFactory.getLogger(ChartSession.class);private WebSocketSession session;@Overridepublic void onClose() {logger.info("{} exit",name);sessions.remove(name);}@Overridepublic void setWebSocketSession(WebSocketSession session) {this.session = session;}@Overridepublic void onMessage(byte[] message) {String messageStr;try {messageStr = new String(message,"UTF-8");} catch (UnsupportedEncodingException e) {messageStr = new String(message);}logger.info("{} say : ",messageStr);Iterator iter = sessions.values().iterator();byte[] m;try {m = (name+" say : "+messageStr).getBytes("UTF-8");} catch (UnsupportedEncodingException e1) {m = (name+" say : "+messageStr).getBytes();}while(iter.hasNext()){ChartSession s = iter.next();try {s.sendText(m, 1, TimeUnit.SECONDS, null);} catch (InterruptedException e) {}}}@Overridepublic Future sendText(byte[] bytes, long timeout, TimeUnit unit,WebSocketCallback callback) throws InterruptedException {return session.sendText(bytes, timeout, unit, callback);}@Overridepublic Future sendBinary(byte[] bytes, long timeout, TimeUnit unit,WebSocketCallback callback) throws InterruptedException {// TODO Auto-generated method stubreturn session.sendBinary(bytes, timeout, unit, callback);}@Overridepublic Future close(WebSocketCallback callback, long timeout,TimeUnit unit) throws InterruptedException {// TODO Auto-generated method stubreturn session.close(callback, timeout, unit);}
}