package cn.liangjintang.httpproxy; import java.io.BufferedReader; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.OutputStream; import java.net.ServerSocket; import java.net.Socket; public class HttpProxy {  static long threadCount = 0;  int myTcpPort = 8080;  private ServerSocket myServerSocket;  private Thread myThread;  public HttpProxy(int port) throws IOException {   myTcpPort = port;   myServerSocket = new ServerSocket(myTcpPort);   myThread = new Thread(new Runnable() {    public void run() {     try {      while (true)       new HTTPSession(myServerSocket.accept());     } catch (IOException ioe) {     }    }   });   myThread.setDaemon(true);   myThread.start();  }  /**   * Stops the server.   */  public void stop() {   try {    myServerSocket.close();    myThread.join();   } catch (IOException ioe) {   } catch (InterruptedException e) {   }  }  public class HTTPSession implements Runnable {   private Socket mySocket;   public HTTPSession(Socket s) {    mySocket = s;    Thread t = new Thread(this);    t.setDaemon(true);    t.start();   }   @Override   public void run() {    try {     ++threadCount;     InputStream is = mySocket.getInputStream();     if (is == null)      return;     final int bufsize = 8192;     byte[] buf = new byte[bufsize];     int splitbyte = 0;     int rlen = 0;     {      int read = is.read(buf, 0, bufsize);      while (read > 0) {       rlen += read;       splitbyte = findHeaderEnd(buf, rlen);       if (splitbyte > 0)        break;       read = is.read(buf, rlen, bufsize - rlen);      }      ByteArrayInputStream hbis = new ByteArrayInputStream(buf,        0, rlen);      BufferedReader hin = new BufferedReader(        new InputStreamReader(hbis));      Host host = new Host();      {       String string;       boolean flag = false;       while ((string = hin.readLine()) != null) {        if (string.toLowerCase().startsWith("host:")) {         host.host = string;         flag = true;        }        System.out.println(string);       }       if (!flag) {        mySocket.getOutputStream().write(          "error!".getBytes());        mySocket.close();        return;       }      }      host.cal();      System.out.println("address:[" + host.address + "]port:"        + host.port + "\n-------------------\n");      try {       pipe(buf, rlen, mySocket, mySocket.getInputStream(),         mySocket.getOutputStream(), host);      } catch (Exception e) {       System.out.println("Run Exception!");       e.printStackTrace();      }     }    } catch (Exception e) {    }    System.out.println("threadcount:" + --threadCount);   }   /**    * finad http header    **/   private int findHeaderEnd(final byte[] buf, int rlen) {    int splitbyte = 0;    while (splitbyte + 3 < rlen) {     if (buf[splitbyte] == '\r' && buf[splitbyte + 1] == '\n'       && buf[splitbyte + 2] == '\r'       && buf[splitbyte + 3] == '\n')      return splitbyte + 4;     splitbyte++;    }    return 0;   }   void pipe(byte[] request, int requestLen, Socket client,     InputStream clientIS, OutputStream clientOS, Host host)     throws Exception {    byte bytes[] = new byte[1024 * 32];    Socket socket = new Socket(host.address, host.port);    socket.setSoTimeout(3000);    OutputStream os = socket.getOutputStream();    InputStream is = socket.getInputStream();    try {     do {      os.write(request, 0, requestLen);      int resultLen = 0;      try {       while ((resultLen = is.read(bytes)) != -1         && !mySocket.isClosed() && !socket.isClosed()) {        clientOS.write(bytes, 0, resultLen);       }      } catch (Exception e) {       System.out.println("target Socket exception:"         + e.toString());      }      System.out.println("proxy requset-connect broken,socket:"        + socket.hashCode());     } while (!mySocket.isClosed()       && (requestLen = clientIS.read(request)) != -1);    } catch (Exception e) {     System.out.println("client Socket exception:" + e.toString());    }    System.out.println("end,socket:" + socket.hashCode());    os.close();    is.close();    clientIS.close();    clientOS.close();    socket.close();    mySocket.close();   }   // target Host info   final class Host {    public String address;    public int port;    public String host;    public boolean cal() {     if (host == null)      return false;     int start = host.indexOf(": ");     if (start == -1)      return false;     int next = host.indexOf(':', start + 2);     if (next == -1) {      port = 80;      address = host.substring(start + 2);     } else {      address = host.substring(start + 2, next);      port = Integer.valueOf(host.substring(next + 1));     }     return true;    }   }  }  public static void main(String[] args) {   try {    new HttpProxy(8580);   } catch (IOException ioe) {    System.err.println("Couldn't start server:\n" + ioe);    System.exit(-1);   }   System.out.println("start!");   try {    System.in.read();   } catch (Throwable t) {   }   System.out.println("stop!");  } }