java使用apache commons连接ftp修改ftp文件名失败原因

package net.codejava.ftp;import java.io.IOException;import org.apache.commons.net.ftp.FTPClient;public class FTPRenamer {  public static void main(String[] args) {    String server = "www.ftpserver.com";    int port = 21;    String user = "username";    String pass = "password";    FTPClient ftpClient = new FTPClient();    try {      ftpClient.connect(server, port);      ftpClient.login(user, pass);      // renaming directory      String oldDir = "/photo";      String newDir = "/photo_2012";      boolean success = ftpClient.rename(oldDir, newDir);      if (success) {        System.out.println(oldDir + " was successfully renamed to: "            + newDir);      } else {        System.out.println("Failed to rename: " + oldDir);      }      // renaming file      String oldFile = "/work/error.png";      String newFile = "/work/screenshot.png";      success = ftpClient.rename(oldFile, newFile);      if (success) {        System.out.println(oldFile + " was successfully renamed to: "            + newFile);      } else {        System.out.println("Failed to rename: " + oldFile);      }      ftpClient.logout();      ftpClient.disconnect();    } catch (IOException ex) {      ex.printStackTrace();    } finally {      if (ftpClient.isConnected()) {        try {          ftpClient.logout();          ftpClient.disconnect();        } catch (IOException ex) {          ex.printStackTrace();        }      }    }  }}如果修改的名字里没有中文，用上面的代码就够了，但如果有中文就要对文件名进行转码了，转码代码如下// renaming fileString oldFile = "/work/你好.png";String newFile = "/work/世界.png";success = ftpClient.rename(  new String(oldFile.getBytes(StandardCharsets.UTF_8), StandardCharsets.ISO_8859_1),  new String(newFile.getBytes(StandardCharsets.UTF_8), StandardCharsets.ISO_8859_1));

import java.io.File;import java.io.FileInputStream;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;/** * A program that demonstrates how to upload files from local computer * to a remote FTP server using Apache Commons Net API. * @author www.codejava.net */public class FTPUploadFileDemo {  public static void main(String[] args) {    String server = "www.myserver.com";    int port = 21;    String user = "user";    String pass = "pass";    FTPClient ftpClient = new FTPClient();    try {      ftpClient.connect(server, port);      ftpClient.login(user, pass);      ftpClient.enterLocalPassiveMode();      ftpClient.setFileType(FTP.BINARY_FILE_TYPE);      // APPROACH #1: uploads first file using an InputStream      File firstLocalFile = new File("D:/Test/Projects.zip");      String firstRemoteFile = "Projects.zip";      InputStream inputStream = new FileInputStream(firstLocalFile);      System.out.println("Start uploading first file");      boolean done = ftpClient.storeFile(firstRemoteFile, inputStream);      inputStream.close();      if (done) {        System.out.println("The first file is uploaded successfully.");      }      // APPROACH #2: uploads second file using an OutputStream      File secondLocalFile = new File("E:/Test/Report.doc");      String secondRemoteFile = "test/Report.doc";      inputStream = new FileInputStream(secondLocalFile);      System.out.println("Start uploading second file");      OutputStream outputStream = ftpClient.storeFileStream(secondRemoteFile);      byte[] bytesIn = new byte[4096];      int read = 0;      while ((read = inputStream.read(bytesIn)) != -1) {        outputStream.write(bytesIn, 0, read);      }      inputStream.close();      outputStream.close();      boolean completed = ftpClient.completePendingCommand();      if (completed) {        System.out.println("The second file is uploaded successfully.");      }    } catch (IOException ex) {      System.out.println("Error: " + ex.getMessage());      ex.printStackTrace();    } finally {      try {        if (ftpClient.isConnected()) {          ftpClient.logout();          ftpClient.disconnect();        }      } catch (IOException ex) {        ex.printStackTrace();      }    }  }}

import java.io.BufferedOutputStream;import java.io.File;import java.io.FileInputStream;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;/** * A program demonstrates how to upload files from local computer to a remote * FTP server using Apache Commons Net API. * @author www.codejava.net */public class FTPDownloadFileDemo {  public static void main(String[] args) {    String server = "www.myserver.com";    int port = 21;    String user = "user";    String pass = "pass";    FTPClient ftpClient = new FTPClient();    try {      ftpClient.connect(server, port);      ftpClient.login(user, pass);      ftpClient.enterLocalPassiveMode();      ftpClient.setFileType(FTP.BINARY_FILE_TYPE);      // APPROACH #1: using retrieveFile(String, OutputStream)      String remoteFile1 = "/test/video.mp4";      File downloadFile1 = new File("D:/Downloads/video.mp4");      OutputStream outputStream1 = new BufferedOutputStream(new FileOutputStream(downloadFile1));      boolean success = ftpClient.retrieveFile(remoteFile1, outputStream1);      outputStream1.close();      if (success) {        System.out.println("File #1 has been downloaded successfully.");      }      // APPROACH #2: using InputStream retrieveFileStream(String)      String remoteFile2 = "/test/song.mp3";      File downloadFile2 = new File("D:/Downloads/song.mp3");      OutputStream outputStream2 = new BufferedOutputStream(new FileOutputStream(downloadFile2));      InputStream inputStream = ftpClient.retrieveFileStream(remoteFile2);      byte[] bytesArray = new byte[4096];      int bytesRead = -1;      while ((bytesRead = inputStream.read(bytesArray)) != -1) {        outputStream2.write(bytesArray, 0, bytesRead);      }      success = ftpClient.completePendingCommand();      if (success) {        System.out.println("File #2 has been downloaded successfully.");      }      outputStream2.close();      inputStream.close();    } catch (IOException ex) {      System.out.println("Error: " + ex.getMessage());      ex.printStackTrace();    } finally {      try {        if (ftpClient.isConnected()) {          ftpClient.logout();          ftpClient.disconnect();        }      } catch (IOException ex) {        ex.printStackTrace();      }    }  }}

import java.io.IOException;import org.apache.commons.net.ftp.FTPClient;import org.apache.commons.net.ftp.FTPReply;public class FTPDeleteFileDemo {  public static void main(String[] args) {    String server = "www.myserver.com";    int port = 21;    String user = "user";    String pass = "pass";    FTPClient ftpClient = new FTPClient();    try {      ftpClient.connect(server, port);      int replyCode = ftpClient.getReplyCode();      if (!FTPReply.isPositiveCompletion(replyCode)) {        System.out.println("Connect failed");        return;      }      boolean success = ftpClient.login(user, pass);      if (!success) {        System.out.println("Could not login to the server");        return;      }      String fileToDelete = "/repository/video/cool.mp4";      boolean deleted = ftpClient.deleteFile(fileToDelete);      if (deleted) {        System.out.println("The file was deleted successfully.");      } else {        System.out.println("Could not delete the file, it may not exist.");      }    } catch (IOException ex) {      System.out.println("Oh no, there was an error: " + ex.getMessage());      ex.printStackTrace();    } finally {      // logs out and disconnects from server      try {        if (ftpClient.isConnected()) {          ftpClient.logout();          ftpClient.disconnect();        }      } catch (IOException ex) {        ex.printStackTrace();      }    }  }}

package net.codejava.ftp;import java.io.IOException;import java.io.InputStream;import java.net.SocketException;import org.apache.commons.net.ftp.FTPClient;import org.apache.commons.net.ftp.FTPReply;/** * This program demonstrates how to determine existence of a specific * file/directory on a remote FTP server. * @author www.codejava.net * */public class FTPCheckFileExists {  private FTPClient ftpClient;  private int returnCode;  /**   * Determines whether a directory exists or not   * @param dirPath   * @return true if exists, false otherwise   * @throws IOException thrown if any I/O error occurred.   */  boolean checkDirectoryExists(String dirPath) throws IOException {    ftpClient.changeWorkingDirectory(dirPath);    returnCode = ftpClient.getReplyCode();    if (returnCode == 550) {      return false;    }    return true;  }  /**   * Determines whether a file exists or not   * @param filePath   * @return true if exists, false otherwise   * @throws IOException thrown if any I/O error occurred.   */  boolean checkFileExists(String filePath) throws IOException {    InputStream inputStream = ftpClient.retrieveFileStream(filePath);    returnCode = ftpClient.getReplyCode();    if (inputStream == null || returnCode == 550) {      return false;    }    return true;  }  /**   * Connects to a remote FTP server   */  void connect(String hostname, int port, String username, String password)      throws SocketException, IOException {    ftpClient = new FTPClient();    ftpClient.connect(hostname, port);    returnCode = ftpClient.getReplyCode();    if (!FTPReply.isPositiveCompletion(returnCode)) {      throw new IOException("Could not connect");    }    boolean loggedIn = ftpClient.login(username, password);    if (!loggedIn) {      throw new IOException("Could not login");    }    System.out.println("Connected and logged in.");  }  /**   * Logs out and disconnects from the server   */  void logout() throws IOException {    if (ftpClient != null && ftpClient.isConnected()) {      ftpClient.logout();      ftpClient.disconnect();      System.out.println("Logged out");    }  }  /**   * Runs this program   */  public static void main(String[] args) {    String hostname = "www.yourserver.com";    int port = 21;    String username = "your_user";    String password = "your_password";    String dirPath = "Photo";    String filePath = "Music.mp4";    FTPCheckFileExists ftpApp = new FTPCheckFileExists();    try {      ftpApp.connect(hostname, port, username, password);      boolean exist = ftpApp.checkDirectoryExists(dirPath);      System.out.println("Is directory " + dirPath + " exists? " + exist);      exist = ftpApp.checkFileExists(filePath);      System.out.println("Is file " + filePath + " exists? " + exist);    } catch (IOException ex) {      ex.printStackTrace();    } finally {      try {        ftpApp.logout();      } catch (IOException ex) {        ex.printStackTrace();      }    }  }}