package ex01.pyrmont;import java.net.Socket;
import java.net.ServerSocket;
import java.net.InetAddress;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.IOException;
import java.io.File;public class HttpServer {/*** WEB_ROOT是HTML和其它文件存放的目录. 这里的WEB_ROOT为工作目录下的webroot目录*/public static final String WEB_ROOT = System.getProperty("user.dir") + File.separator + "webroot";// 关闭服务命令private static final String SHUTDOWN_COMMAND = "/SHUTDOWN";public static void main(String[] args) {HttpServer server = new HttpServer();//等待连接请求
        server.await();}public void await() {ServerSocket serverSocket = null;int port = 8080;try {//服务器套接字对象serverSocket = new ServerSocket(port, 1, InetAddress.getByName("127.0.0.1"));} catch (IOException e) {e.printStackTrace();System.exit(1);}// 循环等待一个请求while (true) {Socket socket = null;InputStream input = null;OutputStream output = null;try {//等待连接，连接成功后，返回一个Socket对象socket = serverSocket.accept();input = socket.getInputStream();output = socket.getOutputStream();// 创建Request对象并解析Request request = new Request(input);request.parse();// 检查是否是关闭服务命令if (request.getUri().equals(SHUTDOWN_COMMAND)) {break;}// 创建 Response 对象Response response = new Response(output);response.setRequest(request);response.sendStaticResource();// 关闭 socket 对象
                socket.close();} catch (Exception e) {e.printStackTrace();continue;}}}
}

package ex01.pyrmont;import java.io.InputStream;
import java.io.IOException;public class Request {private InputStream input;private String uri;public Request(InputStream input) {this.input = input;}//从InputStream中读取request信息，并从request中获取uri值public void parse() {StringBuffer request = new StringBuffer(2048);int i;byte[] buffer = new byte[2048];try {i = input.read(buffer);} catch (IOException e) {e.printStackTrace();i = -1;}for (int j = 0; j < i; j++) {request.append((char) buffer[j]);}System.out.print(request.toString());uri = parseUri(request.toString());}/*** * requestString形式如下：* GET /index.html HTTP/1.1* Host: localhost:8080* Connection: keep-alive* Cache-Control: max-age=0* ...* 该函数目的就是为了获取/index.html字符串*/private String parseUri(String requestString) {int index1, index2;index1 = requestString.indexOf(' ');if (index1 != -1) {index2 = requestString.indexOf(' ', index1 + 1);if (index2 > index1)return requestString.substring(index1 + 1, index2);}return null;}public String getUri() {return uri;}}

package ex01.pyrmont;import java.io.OutputStream;
import java.io.IOException;
import java.io.FileInputStream;
import java.io.File;/*HTTP Response = Status-Line*(( general-header | response-header | entity-header ) CRLF)CRLF[ message-body ]Status-Line = HTTP-Version SP Status-Code SP Reason-Phrase CRLF
*/public class Response {private static final int BUFFER_SIZE = 1024;Request request;OutputStream output;public Response(OutputStream output) {this.output = output;}public void setRequest(Request request) {this.request = request;}public void sendStaticResource() throws IOException {byte[] bytes = new byte[BUFFER_SIZE];FileInputStream fis = null;try {//将web文件写入到OutputStream字节流中File file = new File(HttpServer.WEB_ROOT, request.getUri());if (file.exists()) {fis = new FileInputStream(file);int ch = fis.read(bytes, 0, BUFFER_SIZE);while (ch != -1) {output.write(bytes, 0, ch);ch = fis.read(bytes, 0, BUFFER_SIZE);}} else {// file not foundString errorMessage = "HTTP/1.1 404 File Not Found\r\n" + "Content-Type: text/html\r\n"+ "Content-Length: 23\r\n" + "\r\n" + "<h1>File Not Found</h1>";output.write(errorMessage.getBytes());}} catch (Exception e) {// thrown if cannot instantiate a File object
            System.out.println(e.toString());} finally {if (fis != null)fis.close();}}
}