ftpserver.java

《Java实例入门》所有实例的源代码。所有的源文件都是.java文件

import java.io.*;
import java.net.*;

public class ftpServer extends Thread{
   private Socket socketClient;
   private int counter;
   private static String initDir;

   public static void main(String[] args){
           if(args.length != 0) {
                 initDir = args[0];
            }else{ initDir = "c:";}
           int i = 1;
           try{
                 System.out.println("ftp server started!");
                 //监听21号端口
                 ServerSocket s = new ServerSocket(21);

                for(;;){
                      //接受客户端请求
                      Socket incoming = s.accept();
                      //创建服务线程
                    new ftpServer(incoming,i).start();
                      i++;
                 }
            }catch(Exception e){}
      }

      //构造方法
      public ftpServer(Socket income, int c){
             socketClient = income;
             counter = c;
      }


       public void run(){
          int  tempPort=1;
          int  portClient;
           String user="",host,dir;
           System.out.println(initDir);
           dir = initDir;
           InetAddress clientAddress;
           InetAddress localAddress;
          try{
              //得到客户端地址
              clientAddress =socketClient.getInetAddress();
              //本地地址
              localAddress=socketClient.getLocalAddress() ;
              //得到客户端端口
              portClient=socketClient.getPort();
              host =clientAddress.toString();
              host = host.substring(host.indexOf("/") + 1);
              //输出客户端信息
              System.out.println("client no "+counter+" is "+host+":"+portClient);
              //创建输入流
              BufferedReader in
               = new BufferedReader(new InputStreamReader(socketClient.getInputStream()));
              //创建输出流
              PrintWriter out
               = new PrintWriter(socketClient.getOutputStream(),true);
              //发送欢迎信息
              out.println("Welcome! 220 FTP server[JAVA FTP server]ready.\r");

              boolean done = false;
              while(!done){
                    String str = in.readLine();
          if(str.startsWith("RETR")){
                        out.println("150 Binary data connection");
                        str = str.substring(4);
                        str = str.trim();
                        RandomAccessFile outFile = new
                        RandomAccessFile(dir+"/"+str,"r");

                        Socket tempSocket = new Socket(host,tempPort);
                        OutputStream outSocket
                           = tempSocket.getOutputStream();
                        byte byteBuffer[]= new byte[1024];
                        int amount;
                       try{
                            while((amount = outFile.read(byteBuffer)) != -1){
                                   outSocket.write(byteBuffer, 0, amount);

                          }
                        outSocket.close();
                        out.println("226 transfer complete");
                        outFile.close();
                        tempSocket.close();
                       }
                        catch(IOException e){}
                  }

          if(str.startsWith("STOR")){
                        out.println("150 Binary data connection");
                        str = str.substring(4);
                        str = str.trim();
                        RandomAccessFile inFile = new
                        RandomAccessFile(dir+"/"+str,"rw");
                        Socket tempSocket = new Socket(host,tempPort);
                        InputStream inSocket
                           = tempSocket.getInputStream();
                      byte byteBuffer[] = new byte[1024];
                      int amount;
                       try{
                        while((amount =inSocket.read(byteBuffer) )!= -1){
                              inFile.write(byteBuffer, 0, amount);
                          }
                        inSocket.close();
                        out.println("226 transfer complete");
                        inFile.close();
                        tempSocket.close();
                       }
                        catch(IOException e){}
                  }


          if(str.startsWith("TYPE")){
                        out.println("200 type set");}
          if(str.startsWith("DELE")){
                        str = str.substring(4);
                        str = str.trim();
                        File file = new File(dir,str);
                       boolean del = file.delete();
                        out.println("250 delete command successful");}

          if(str.startsWith("CDUP")){
                      int n = dir.lastIndexOf("/");
                        dir = dir.substring(0,n);
                        out.println("250 CWD command succesful");
                                     }
          if(str.startsWith("CWD")){
                        String str1 = str.substring(3);
                        dir = dir+"/"+str1.trim();
                        out.println("250 CWD command succesful");
                                     }
          if(str.startsWith("QUIT")) {
                        out.println("GOOD BYE");
                        done = true; }
          if(str.startsWith("USER")){
                        user = str.substring(4);
                        user = user.trim();
                        out.println("331 Password");}
          if(str.startsWith("PASS"))
                        out.println("230 User "+user+" logged in.");
          if(str.startsWith("XPWD")){
                        out.println("257 \""+dir+"\" is current directory");
            }
          if(str.startsWith("SYS"))
                        out.println("500 SYS not understood");
          if(str.startsWith("PORT")) {
                        out.println("200 PORT command successful");
                      int i = str.length() - 1;
                      int j = str.lastIndexOf(",");
                      int k = str.lastIndexOf(",",j-1);
                        String str1,str2;
                        str1="";
                        str2="";
                      for(int l=k+1;l<j;l++){
                             str1 = str2 + str.charAt(l);
                        }
                      for(int l=j+1;l<=i;l++){
                              str2 = str2 + str.charAt(l);
                        }
                        tempPort = Integer.parseInt(str1) * 16 *16 +Integer.parseInt(str2);
          }
          if(str.startsWith("LIST")) {
                        try{
                             out.println("150 ASCII data");
                             Socket tempSocket = new Socket(host,tempPort);
                             PrintWriter out2
                                 = new PrintWriter(tempSocket.getOutputStream(),true);

                              File file = new File(dir);
                              String[] dirStructure = new String[10];
                              dirStructure= file.list();
                              String strType="";
                           for(int i=0;i<dirStructure.length;i++){
                              if( dirStructure[i].indexOf(".") == -1)    // DIR
                                    {strType = "d ";}
                               else
                                    {strType = "- ";}
                                 out2.println(strType+dirStructure[i]);
                             }
                           tempSocket.close();
                           out.println("226 transfer complete");
                           }catch(IOException e){
                           }
                       }

           }
           socketClient.close();
        }
        catch (Exception e){
             System.out.println(e);
        }
     }
}