使用Java实现一个最简单的Web Server Java

Hello Web Server Web Server没有你想象的那么难实现（当然要实现一个好的Java Web Server还是很有难度的）。你只要明白基本的HTTP协议，TCP编程和IO知识。当然，你也要会最简单的HTML代码。
我们先来一个屌丝版，这个屌丝版能显示Hello Web Server

package exec.network.webserver; import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.IOException; import java.io.InputStreamReader; import java.io.OutputStreamWriter; import java.net.ServerSocket; import java.net.Socket; public class SimpleHttpServer { private final static int TCP_PORT = 9090; public static void main(String[] args) throws IOException { ServerSocket ss = new ServerSocket(TCP_PORT); Socket socket = ss.accept(); BufferedReader br = new BufferedReader( new InputStreamReader(socket.getInputStream())); String buffer = null; while ((buffer = br.readLine()) != null && !s.equals("")) { System.out.println(buffer); }BufferedWriter bw = new BufferedWriter( new OutputStreamWriter(socket.getOutputStream())); bw.write("HTTP/1.1 200 OK\n"); bw.write("Content-Type: text/html; charset=UTF-8\n\n"); bw.write("\n" + "\n" + "first page - 锐客网\n" + "\n" + "\n" + "Hello Web Server!\n" + "\n" + "\n"); bw.flush(); bw.close(); br.close(); socket.close(); ss.close(); } }

运行这个程序，然后再浏览器里敲：http://localhost:9090/，页面上会出现一个大大的Hello Web Server。然后，就没有然后了……
静态网页版看了上面的程序，你可能都会说，太屌丝了，不行，继续。
【使用Java实现一个最简单的Web Server】我们来加强这个Web Server。
准备示例的静态页面文件准备一个webroot文件夹，里面放个index.htm文件，再准备一个01.jpg文件，作为图片放进去。这个是我们准备的index.htm，图片就不展示了。

Document - 锐客网 HTTP SERVER Where there is a will, there is a way. 文章图片

准备HttpServer和Request，Response程序

HttpServer

package exec.network.webserver; import java.io.File; import java.io.InputStream; import java.io.OutputStream; import java.net.ServerSocket; import java.net.Socket; public class HttpServer { private static final int SERVER_PORT = 9090; public static final String WEB_ROOT = System.getProperty("user.dir") + File.separator + "webroot"; private static final String SHUTDOWN_COMMAND = "/QUIT"; public static void main(String[] args) { HttpServer server = new HttpServer(); server.await(); }public void await() { ServerSocket serverSocket = null; try { serverSocket = new ServerSocket(SERVER_PORT); } catch (Exception e) { e.printStackTrace(); System.exit(1); }while(true) { Socket socket = null; InputStream input = null; OutputStream output = null; try { 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(); } } }}

Request

package exec.network.webserver; import java.io.InputStream; public class Request { private final static int BUFFER_SIZE = 1024; private InputStream input; private String uri; public Request(InputStream input) { this.input = input; }public void parse() { StringBuffer request = new StringBuffer(); int readLength; byte[] buffer = new byte[BUFFER_SIZE]; try { readLength = input.read(buffer); } catch (Exception e) { e.printStackTrace(); readLength = -1; } for(int i = 0; i < readLength; i++) { request.append((char)buffer[i]); } System.out.print(request.toString()); uri = parseUri(request.toString()); }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; } }

Response

package exec.network.webserver; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.OutputStream; 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[] buffer = new byte[BUFFER_SIZE]; FileInputStream fis = null; try { File file = new File( HttpServer.WEB_ROOT, request.getUri()); if(file.exists()) { output.write("HTTP/1.1 200 OK\n".getBytes()); output.write("Content-Type: text/html; charset=UTF-8\n\n".getBytes()); fis = new FileInputStream(file); int readLength; while((readLength = fis.read(buffer, 0, BUFFER_SIZE)) > 0 ) { output.write(buffer, 0, readLength); } } else { String errMsg = "HTTP/1.1 404 File Not Found\r\n" + "Content-Type: text/html\r\n" + "Content-Length: 23\r\n" + "\r\n" + "File Not Found"; output.write(errMsg.getBytes()); } } catch (Exception e) { e.printStackTrace(); } finally { if(fis != null) { fis.close(); } } } }

好了，最简单的Web Server我们已经用Java实现了，简单吧。
参考资料 http://www.cnblogs.com/chenpi/p/5602171.html