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();
    }
}

原文地址：http://www.cnblogs.com/winorgohome/archive/2016/11/22/6088013.html