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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