Java Code Examples for org.apache.commons.net.ftp.FTPClient#retrieveFile()

public static void download(String ftpUrl, String localFilePath, String ftpUsername, String ftpPassword, String ftpControlEncoding) throws IOException {
    String username = StringUtils.isEmpty(ftpUsername) ? ConfigConstants.getFtpUsername() : ftpUsername;
    String password = StringUtils.isEmpty(ftpPassword) ? ConfigConstants.getFtpPassword() : ftpPassword;
    String controlEncoding = StringUtils.isEmpty(ftpControlEncoding) ? ConfigConstants.getFtpControlEncoding() : ftpControlEncoding;
    URL url = new URL(ftpUrl);
    String host = url.getHost();
    int port = (url.getPort() == -1) ? url.getDefaultPort() : url.getPort();
    String remoteFilePath = url.getPath();
    LOGGER.debug("FTP connection url:{}, username:{}, password:{}, controlEncoding:{}, localFilePath:{}", ftpUrl, username, password, controlEncoding, localFilePath);
    FTPClient ftpClient = connect(host, port, username, password, controlEncoding);
    OutputStream outputStream = new FileOutputStream(localFilePath);
    ftpClient.enterLocalPassiveMode();
    boolean downloadResult = ftpClient.retrieveFile(new String(remoteFilePath.getBytes(controlEncoding), StandardCharsets.ISO_8859_1), outputStream);
    LOGGER.debug("FTP download result {}", downloadResult);
    outputStream.flush();
    outputStream.close();
    ftpClient.logout();
    ftpClient.disconnect();
}
 

public static void getDataFile(
    FTPFile[] files, String destinationFolder, Calendar start, Calendar end, FTPClient ftp) {
  for (int i = 0; i < files.length; i++) {

    Date fileDate = files[i].getTimestamp().getTime();
    if (fileDate.compareTo(start.getTime()) >= 0 && fileDate.compareTo(end.getTime()) <= 0) {

      // Download a file from the FTP Server
      File file = new File(destinationFolder + File.separator + files[i].getName());
      try (FileOutputStream fos = new FileOutputStream(file); ) {
        ftp.retrieveFile(files[i].getName(), fos);
        file.setLastModified(fileDate.getTime());
      } catch (Exception e) {
        LOG.error(e.getMessage());
        TraceBackService.trace(e);
      }
    }
  }
}
 

/**
 *  FTP下载文件 到 输出流
 * @param path ftp文件路径 
 * @param ops  
 * @return 是否写入成功
 */
public boolean downloadFile(String path, OutputStream ops)  {
	FTPClient ftpClient = borrowObject();
	try {
		boolean result = ftpClient.retrieveFile(path, ops);
		return result;
	} catch (IOException e) {
		e.printStackTrace();
		throw new RuntimeException(e);
	}finally {
		returnObject(ftpClient);
	}
}
 

/** 
 * 下载一个远程文件到指定的流 处理完后记得关闭流 
 *  
 * @param remoteAbsoluteFile 
 * @param output 
 * @param
 * @return 
 * @throws Exception
 */  
public boolean get(String remoteAbsoluteFile, OutputStream output, boolean autoClose) throws Exception {
    try {  
        FTPClient ftpClient = getFTPClient();
        // 处理传输  
        return ftpClient.retrieveFile(remoteAbsoluteFile, output);  
    } catch (IOException e) {
        throw new Exception("Couldn't get file from server.", e);
    } finally {  
        if (autoClose) {  
            disconnect(); //关闭链接  
        }  
    }  
}
 

/** 
 * Description: 从FTP服务器下载文件 
 * @param host 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 downloadFile(String host, int port, String username, String password, String remotePath, String fileName, String localPath) {
	boolean result = false;
	FTPClient ftp = new FTPClient();
	try {
		int reply;
		ftp.connect(host, port);
		// 如果采用默认端口，可以使用ftp.connect(host)的方式直接连接FTP服务器
		ftp.login(username, password);// 登录
		reply = ftp.getReplyCode();
		if (!FTPReply.isPositiveCompletion(reply)) {
			ftp.disconnect();
			return result;
		}
		ftp.changeWorkingDirectory(remotePath);// 转移到FTP服务器目录
		FTPFile[] fs = ftp.listFiles();
		for (FTPFile ff : fs) {
			if (ff.getName().equals(fileName)) {
				File localFile = new File(localPath + "/" + ff.getName());

				OutputStream is = new FileOutputStream(localFile);
				ftp.retrieveFile(ff.getName(), is);
				is.close();
			}
		}

		ftp.logout();
		result = true;
	} catch (IOException e) {
		e.printStackTrace();
	} finally {
		if (ftp.isConnected()) {
			try {
				ftp.disconnect();
			} catch (IOException ioe) {
			}
		}
	}
	return result;
}
 

static byte[] loadFTPArchive(final String host, final String path, final String name,
                             final String password) throws IOException {
  final FTPClient client = new FTPClient();
  client.connect(host);
  int replyCode = client.getReplyCode();

  if (FTPReply.isPositiveCompletion(replyCode)) {
    try {
      client.login(name == null ? "" : name, password == null ? "" : password);
      client.setFileType(FTP.BINARY_FILE_TYPE);
      client.enterLocalPassiveMode();

      final ByteArrayOutputStream out = new ByteArrayOutputStream(300000);
      if (client.retrieveFile(path, out)) {
        return out.toByteArray();
      } else {
        throw new IOException(
            "Can't load file 'ftp://" + host + path + "\' status=" + client.getReplyCode());
      }
    } finally {
      client.disconnect();
    }
  } else {
    client.disconnect();
    throw new IOException("Can't connect to ftp '" + host + "'");
  }
}
 

public File retrieve(String name,String fileName) throws IOException {
	String path = System.getProperty("java.io.tmpdir");
	File file = new File(path, fileName);
	file = UploadUtils.getUniqueFile(file);

	FTPClient ftp = getClient();
	OutputStream output = new FileOutputStream(file);
	ftp.retrieveFile(getPath() + name, output);
	output.close();
	ftp.logout();
	ftp.disconnect();
	return file;
}
 

private void retrieveFile(FTPClient ftp, String remoteFilePath, OutputStream out) throws IOException, FTPException {
    ftp.retrieveFile(remoteFilePath, out);
    checkReply("get " + remoteFilePath, ftp);
}