Java实现FTP文件与文件夹的上传和下载

ftp 是file transfer protocol（文件传输协议）的英文简称，而中文简称为“文传协议”。用于internet上的控制文件的双向传输。同时，它也是一个应用程序（application）。基于不同的操作系统有不同的ftp应用程序，而所有这些应用程序都遵守同一种协议以传输文件。在ftp的使用当中，用户经常遇到两个概念："下载"（download）和"上传"（upload）。"下载"文件就是从远程主机拷贝文件至自己的计算机上；"上传"文件就是将文件从自己的计算机中拷贝至远程主机上。用internet语言来说，用户可通过客户机程序向（从）远程主机上传（下载）文件。

首先下载了serv-u将自己的电脑设置为了ftp文件服务器，方便操作。下面代码的使用都是在ftp服务器已经创建，并且要在代码中写好ftp连接的相关数据才可以完成。

1.ftp文件的上传与下载(注意是单个文件的上传与下载)

import java.io.file;
import java.io.fileinputstream;
import java.io.filenotfoundexception;
import java.io.fileoutputstream;
import java.io.ioexception;
import java.io.inputstream;
import java.io.outputstream;
import org.apache.commons.net.ftp.ftp;
import org.apache.commons.net.ftp.ftpclient;
import org.apache.commons.net.ftp.ftpfile;
import org.apache.commons.net.ftp.ftpreply;
/**
 * 实现ftp文件上传和文件下载
 */
public class ftpapche {
 private static ftpclient ftpclient = new ftpclient();
 private static string encoding = system.getproperty("file.encoding");
 /**
  * description: 向ftp服务器上传文件
  * 
  * @version1.0
  * @param url
  *   ftp服务器hostname
  * @param port
  *   ftp服务器端口
  * @param username
  *   ftp登录账号
  * @param password
  *   ftp登录密码
  * @param path
  *   ftp服务器保存目录,如果是根目录则为“/”
  * @param filename
  *   上传到ftp服务器上的文件名
  * @param input
  *   本地文件输入流
  * @return 成功返回true，否则返回false
  */
 public static boolean uploadfile(string url, int port, string username,
   string password, string path, string filename, inputstream input) {
  boolean result = false;
  try {
   int reply;
   // 如果采用默认端口，可以使用ftp.connect(url)的方式直接连接ftp服务器
   ftpclient.connect(url);
   // ftp.connect(url, port);// 连接ftp服务器
   // 登录
   ftpclient.login(username, password);
   ftpclient.setcontrolencoding(encoding);
   // 检验是否连接成功
   reply = ftpclient.getreplycode();
   if (!ftpreply.ispositivecompletion(reply)) {
    system.out.println("连接失败");
    ftpclient.disconnect();
    return result;
   }
   // 转移工作目录至指定目录下
   boolean change = ftpclient.changeworkingdirectory(path);
   ftpclient.setfiletype(ftp.binary_file_type);
   if (change) {
    result = ftpclient.storefile(new string(filename.getbytes(encoding),"iso-8859-1"), input);
    if (result) {
     system.out.println("上传成功!");
    }
   }
   input.close();
   ftpclient.logout();
  } catch (ioexception e) {
   e.printstacktrace();
  } finally {
   if (ftpclient.isconnected()) {
    try {
     ftpclient.disconnect();
    } catch (ioexception ioe) {
    }
   }
  }
  return result;
 }
 /**
  * 将本地文件上传到ftp服务器上
  * 
  */
 public void testuploadfromdisk() {
  try {
   fileinputstream in = new fileinputstream(new file("d:/test02/list.txt"));
   boolean flag = uploadfile("10.0.0.102", 21, "admin","123456", "/", "lis.txt", in);
   system.out.println(flag);
  } catch (filenotfoundexception e) {
   e.printstacktrace();
  }
 }
 /**
  * description: 从ftp服务器下载文件
  * 
  * @version1.0
  * @param url
  *   ftp服务器hostname
  * @param port
  *   ftp服务器端口
  * @param username
  *   ftp登录账号
  * @param password
  *   ftp登录密码
  * @param remotepath
  *   ftp服务器上的相对路径
  * @param filename
  *   要下载的文件名
  * @param localpath
  *   下载后保存到本地的路径
  * @return
  */
 public static boolean downfile(string url, int port, string username,
   string password, string remotepath, string filename,
   string localpath) {
  boolean result = false;
  try {
   int reply;
   ftpclient.setcontrolencoding(encoding);
   /*
    * 为了上传和下载中文文件，有些地方建议使用以下两句代替
    * new string(remotepath.getbytes(encoding),"iso-8859-1")转码。
    * 经过测试，通不过。
    */
//   ftpclientconfig conf = new ftpclientconfig(ftpclientconfig.syst_nt);
//   conf.setserverlanguagecode("zh");
   ftpclient.connect(url, port);
   // 如果采用默认端口，可以使用ftp.connect(url)的方式直接连接ftp服务器
   ftpclient.login(username, password);// 登录
   // 设置文件传输类型为二进制
   ftpclient.setfiletype(ftpclient.binary_file_type);
   // 获取ftp登录应答代码
   reply = ftpclient.getreplycode();
   // 验证是否登陆成功
   if (!ftpreply.ispositivecompletion(reply)) {
    ftpclient.disconnect();
    system.err.println("ftp server refused connection.");
    return result;
   }
   // 转移到ftp服务器目录至指定的目录下
   ftpclient.changeworkingdirectory(new string(remotepath.getbytes(encoding),"iso-8859-1"));
   // 获取文件列表
   ftpfile[] fs = ftpclient.listfiles();
   for (ftpfile ff : fs) {
    if (ff.getname().equals(filename)) {
     file localfile = new file(localpath + "/" + ff.getname());
     outputstream is = new fileoutputstream(localfile);
     ftpclient.retrievefile(ff.getname(), is);
     is.close();
    }
   }
   ftpclient.logout();
   result = true;
  } catch (ioexception e) {
   e.printstacktrace();
  } finally {
   if (ftpclient.isconnected()) {
    try {
     ftpclient.disconnect();
    } catch (ioexception ioe) {
    }
   }
  }
  return result;
 }
 /**
  * 将ftp服务器上文件下载到本地
  * 
  */
 public void testdownfile() {
  try {
   boolean flag = downfile("10.0.0.102", 21, "admin",
     "123456", "/", "ip.txt", "e:/");
   system.out.println(flag);
  } catch (exception e) {
   e.printstacktrace();
  }
 }
 public static void main(string[] args) {
  ftpapche fa = new ftpapche();
  fa.testdownfile();
  fa.testuploadfromdisk();
 }
}

2.ftp文件夹的上传与下载(注意是整个文件夹)

package ftp;
import java.io.bufferedinputstream;
import java.io.bufferedoutputstream;
import java.io.file;
import java.io.fileinputstream;
import java.io.filenotfoundexception;
import java.io.fileoutputstream;
import java.io.ioexception;
import java.util.timezone;
import org.apache.commons.net.ftp.ftpclient;
import org.apache.commons.net.ftp.ftpclientconfig;
import org.apache.commons.net.ftp.ftpfile;
import org.apache.commons.net.ftp.ftpreply;
import org.apache.log4j.logger;
public class ftptest_04 {
 private ftpclient ftpclient;
 private string strip;
 private int intport;
 private string user;
 private string password;
 private static logger logger = logger.getlogger(ftptest_04.class.getname());
 /* * 
  * ftp构造函数 
  */ 
 public ftptest_04(string strip, int intport, string user, string password) {
  this.strip = strip;
  this.intport = intport;
  this.user = user;
  this.password = password;
  this.ftpclient = new ftpclient();
 }
 /** 
  * @return 判断是否登入成功 
  * */ 
 public boolean ftplogin() {
  boolean islogin = false;
  ftpclientconfig ftpclientconfig = new ftpclientconfig();
  ftpclientconfig.setservertimezoneid(timezone.getdefault().getid());
  this.ftpclient.setcontrolencoding("gbk");
  this.ftpclient.configure(ftpclientconfig);
  try {
   if (this.intport > 0) {
    this.ftpclient.connect(this.strip, this.intport);
   }else {
    this.ftpclient.connect(this.strip);
   }
   // ftp服务器连接回答 
   int reply = this.ftpclient.getreplycode();
   if (!ftpreply.ispositivecompletion(reply)) {
    this.ftpclient.disconnect();
    logger.error("登录ftp服务失败！");
    return islogin;
   }
   this.ftpclient.login(this.user, this.password);
   // 设置传输协议 
   this.ftpclient.enterlocalpassivemode();
   this.ftpclient.setfiletype(ftpclient.binary_file_type);
   logger.info("恭喜" + this.user + "成功登陆ftp服务器");
   islogin = true;
  }catch (exception e) {
   e.printstacktrace();
   logger.error(this.user + "登录ftp服务失败！" + e.getmessage());
  }
  this.ftpclient.setbuffersize(1024 * 2);
  this.ftpclient.setdatatimeout(30 * 1000);
  return islogin;
 }
 /** 
  * @退出关闭服务器链接 
  * */ 
 public void ftplogout() {
  if (null != this.ftpclient && this.ftpclient.isconnected()) {
   try {
    boolean reuslt = this.ftpclient.logout();// 退出ftp服务器 
    if (reuslt) {
     logger.info("成功退出服务器");
    }
   }catch (ioexception e) {
    e.printstacktrace();
    logger.warn("退出ftp服务器异常！" + e.getmessage());
   }finally {
    try {
     this.ftpclient.disconnect();// 关闭ftp服务器的连接 
    }catch (ioexception e) {
     e.printstacktrace();
     logger.warn("关闭ftp服务器的连接异常！");
    }
   }
  }
 }
 /*** 
  * 上传ftp文件 
  * @param localfile 当地文件 
  * @param romotuploadepath上传服务器路径 - 应该以/结束 
  * */ 
 public boolean uploadfile(file localfile, string romotuploadepath) {
  bufferedinputstream instream = null;
  boolean success = false;
  try {
   this.ftpclient.changeworkingdirectory(romotuploadepath);// 改变工作路径 
   instream = new bufferedinputstream(new fileinputstream(localfile));
   logger.info(localfile.getname() + "开始上传.....");
   success = this.ftpclient.storefile(localfile.getname(), instream);
   if (success == true) {
    logger.info(localfile.getname() + "上传成功");
    return success;
   }
  }catch (filenotfoundexception e) {
   e.printstacktrace();
   logger.error(localfile + "未找到");
  }catch (ioexception e) {
   e.printstacktrace();
  }finally {
   if (instream != null) {
    try {
     instream.close();
    }catch (ioexception e) {
     e.printstacktrace();
    }
   }
  }
  return success;
 }
 /*** 
  * 下载文件 
  * @param remotefilename 待下载文件名称 
  * @param localdires 下载到当地那个路径下 
  * @param remotedownloadpath remotefilename所在的路径 
  * */ 
 public boolean downloadfile(string remotefilename, string localdires, 
   string remotedownloadpath) {
  string strfilepath = localdires + remotefilename;
  bufferedoutputstream outstream = null;
  boolean success = false;
  try {
   this.ftpclient.changeworkingdirectory(remotedownloadpath);
   outstream = new bufferedoutputstream(new fileoutputstream( 
     strfilepath));
   logger.info(remotefilename + "开始下载....");
   success = this.ftpclient.retrievefile(remotefilename, outstream);
   if (success == true) {
    logger.info(remotefilename + "成功下载到" + strfilepath);
    return success;
   }
  }catch (exception e) {
   e.printstacktrace();
   logger.error(remotefilename + "下载失败");
  }finally {
   if (null != outstream) {
    try {
     outstream.flush();
     outstream.close();
    }catch (ioexception e) {
     e.printstacktrace();
    }
   }
  }
  if (success == false) {
   logger.error(remotefilename + "下载失败!!!");
  }
  return success;
 }
 /*** 
  * @上传文件夹 
  * @param localdirectory 
  *   当地文件夹 
  * @param remotedirectorypath 
  *   ftp 服务器路径 以目录"/"结束 
  * */ 
 public boolean uploaddirectory(string localdirectory, 
   string remotedirectorypath) {
  file src = new file(localdirectory);
  try {
   remotedirectorypath = remotedirectorypath + src.getname() + "/";
   boolean makedirflag = this.ftpclient.makedirectory(remotedirectorypath);
   system.out.println("localdirectory : " + localdirectory);
   system.out.println("remotedirectorypath : " + remotedirectorypath);
   system.out.println("src.getname() : " + src.getname());
   system.out.println("remotedirectorypath : " + remotedirectorypath);
   system.out.println("makedirflag : " + makedirflag);
   // ftpclient.listdirectories();
  }catch (ioexception e) {
   e.printstacktrace();
   logger.info(remotedirectorypath + "目录创建失败");
  }
  file[] allfile = src.listfiles();
  for (int currentfile = 0;currentfile < allfile.length;currentfile++) {
   if (!allfile[currentfile].isdirectory()) {
    string srcname = allfile[currentfile].getpath().tostring();
    uploadfile(new file(srcname), remotedirectorypath);
   }
  }
  for (int currentfile = 0;currentfile < allfile.length;currentfile++) {
   if (allfile[currentfile].isdirectory()) {
    // 递归 
    uploaddirectory(allfile[currentfile].getpath().tostring(), 
      remotedirectorypath);
   }
  }
  return true;
 }
 /*** 
  * @下载文件夹 
  * @param localdirectorypath本地地址 
  * @param remotedirectory 远程文件夹 
  * */ 
 public boolean downloaddirectory(string localdirectorypath,string remotedirectory) {
  try {
   string filename = new file(remotedirectory).getname();
   localdirectorypath = localdirectorypath + filename + "//";
   new file(localdirectorypath).mkdirs();
   ftpfile[] allfile = this.ftpclient.listfiles(remotedirectory);
   for (int currentfile = 0;currentfile < allfile.length;currentfile++) {
    if (!allfile[currentfile].isdirectory()) {
     downloadfile(allfile[currentfile].getname(),localdirectorypath, remotedirectory);
    }
   }
   for (int currentfile = 0;currentfile < allfile.length;currentfile++) {
    if (allfile[currentfile].isdirectory()) {
     string strremotedirectorypath = remotedirectory + "/"+ allfile[currentfile].getname();
     downloaddirectory(localdirectorypath,strremotedirectorypath);
    }
   }
  }catch (ioexception e) {
   e.printstacktrace();
   logger.info("下载文件夹失败");
   return false;
  }
  return true;
 }
 // ftpclient的set 和 get 函数 
 public ftpclient getftpclient() {
  return ftpclient;
 }
 public void setftpclient(ftpclient ftpclient) {
  this.ftpclient = ftpclient;
 }
 public static void main(string[] args) throws ioexception {
  ftptest_04 ftp=new ftptest_04("10.0.0.102",21,"admin","123456");
  ftp.ftplogin();
  system.out.println("1");
  //上传文件夹 
  boolean uploadflag = ftp.uploaddirectory("d:\\test02", "/"); //如果是admin/那么传的就是所有文件，如果只是/那么就是传文件夹
  system.out.println("uploadflag : " + uploadflag);
  //下载文件夹 
  ftp.downloaddirectory("d:\\tm", "/");
  ftp.ftplogout();
 }
}

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