Java使用FTPClient类读写FTP

本文实例为大家分享了Java使用FTPClient类读写FTP的具体代码，供大家参考，具体内容如下

1.首先先导入相关jar包

2.创建一个连接FTP的工具类FTPUtil.java

package com.metarnet.ftp.util; 

import java.io.IOException;
import java.io.InputStream;
import java.net.SocketException;
import java.util.Properties; 

import org.apache.commons.net.ftp.FTPClient;
import org.apache.commons.net.ftp.FTPReply;
import org.apache.log4j.Logger; 

public class FTPUtil {
  private static Logger logger = Logger.getLogger(FTPUtil.class); 

  /**
   * 获取FTPClient对象
   * @param ftpHost FTP主机服务器
   * @param ftpPassword FTP 登录密码
   * @param ftpUserName FTP登录用户名
   * @param ftpPort FTP端口 默认为21
   * @return
   */
  public static FTPClient getFTPClient(String ftpHost, String ftpPassword,
      String ftpUserName, int ftpPort) {
    FTPClient ftpClient = null;
    try {
      ftpClient = new FTPClient();
      ftpClient.connect(ftpHost, ftpPort);// 连接FTP服务器
      ftpClient.login(ftpUserName, ftpPassword);// 登陆FTP服务器
      if (!FTPReply.isPositiveCompletion(ftpClient.getReplyCode())) {
        logger.info("未连接到FTP，用户名或密码错误。");
        ftpClient.disconnect();
      } else {
        logger.info("FTP连接成功。");
      }
    } catch (SocketException e) {
      e.printStackTrace();
      logger.info("FTP的IP地址可能错误，请正确配置。");
    } catch (IOException e) {
      e.printStackTrace();
      logger.info("FTP的端口错误,请正确配置。");
    }
    return ftpClient;
  }
}

3.编写一个读取FTP上文件的类ReadFTPFile.java

package com.metarnet.ftp.read; 

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.SocketException; 

import org.apache.commons.net.ftp.FTPClient;
import org.apache.log4j.Logger; 

import com.metarnet.ftp.util.FTPUtil; 

public class ReadFTPFile {
  private Logger logger = Logger.getLogger(ReadFTPFile.class); 

  /**
   * 去 服务器的FTP路径下上读取文件
   *
   * @param ftpUserName
   * @param ftpPassword
   * @param ftpPath
   * @param FTPServer
   * @return
   */
  public String readConfigFileForFTP(String ftpUserName, String ftpPassword,
      String ftpPath, String ftpHost, int ftpPort, String fileName) {
    StringBuffer resultBuffer = new StringBuffer();
    FileInputStream inFile = null;
    InputStream in = null;
    FTPClient ftpClient = null;
    logger.info("开始读取绝对路径" + ftpPath + "文件!");
    try {
      ftpClient = FTPUtil.getFTPClient(ftpHost, ftpPassword, ftpUserName,
          ftpPort);
      ftpClient.setControlEncoding("UTF-8"); // 中文支持
      ftpClient.setFileType(FTPClient.BINARY_FILE_TYPE);
      ftpClient.enterLocalPassiveMode();
      ftpClient.changeWorkingDirectory(ftpPath);
      in = ftpClient.retrieveFileStream(fileName);
    } catch (FileNotFoundException e) {
      logger.error("没有找到" + ftpPath + "文件");
      e.printStackTrace();
      return "下载配置文件失败，请联系管理员.";
    } catch (SocketException e) {
      logger.error("连接FTP失败.");
      e.printStackTrace();
    } catch (IOException e) {
      e.printStackTrace();
      logger.error("文件读取错误。");
      e.printStackTrace();
      return "配置文件读取失败，请联系管理员.";
    }
    if (in != null) {
      BufferedReader br = new BufferedReader(new InputStreamReader(in));
      String data = null;
      try {
        while ((data = br.readLine()) != null) {
          resultBuffer.append(data + "\n");
        }
      } catch (IOException e) {
        logger.error("文件读取错误。");
        e.printStackTrace();
        return "配置文件读取失败，请联系管理员.";
      }finally{
        try {
          ftpClient.disconnect();
        } catch (IOException e) {
          e.printStackTrace();
        }
      }
    }else{
      logger.error("in为空，不能读取。");
      return "配置文件读取失败，请联系管理员.";
    }
    return resultBuffer.toString();
  }
}

4.创建一个往FTP上写入文件的类WriteFTPFile.java

package com.metarnet.ftp.write; 

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream; 

import org.apache.commons.net.ftp.FTPClient;
import org.apache.commons.net.ftp.FTPFile;
import org.apache.log4j.Logger; 

import com.metarnet.ftp.util.FTPUtil; 

public class WriteFTPFile { 

  private Logger logger = Logger.getLogger(WriteFTPFile.class); 

  /**
   * 本地上传文件到FTP服务器
   *
   * @param ftpPath
   *      远程文件路径FTP
   * @throws IOException
   */
  public void upload(String ftpPath, String ftpUserName, String ftpPassword,
      String ftpHost, int ftpPort, String fileContent,
      String writeTempFielPath) {
    FTPClient ftpClient = null;
    logger.info("开始上传文件到FTP.");
    try {
      ftpClient = FTPUtil.getFTPClient(ftpHost, ftpPassword,
          ftpUserName, ftpPort);
      // 设置PassiveMode传输
      ftpClient.enterLocalPassiveMode();
      // 设置以二进制流的方式传输
      ftpClient.setFileType(FTPClient.BINARY_FILE_TYPE);
      // 对远程目录的处理
      String remoteFileName = ftpPath;
      if (ftpPath.contains("/")) {
        remoteFileName = ftpPath
            .substring(ftpPath.lastIndexOf("/") + 1);
      }
      // FTPFile[] files = ftpClient.listFiles(new
      // String(remoteFileName));
      // 先把文件写在本地。在上传到FTP上最后在删除
      boolean writeResult = write(remoteFileName, fileContent,
          writeTempFielPath);
      if (writeResult) {
        File f = new File(writeTempFielPath + "/" + remoteFileName);
        InputStream in = new FileInputStream(f);
        ftpClient.storeFile(remoteFileName, in);
        in.close();
        logger.info("上传文件" + remoteFileName + "到FTP成功!");
        f.delete();
      } else {
        logger.info("写文件失败!");
      }
    } catch (Exception e) {
      e.printStackTrace();
    }finally{
      try {
        ftpClient.disconnect();
      } catch (IOException e) {
        e.printStackTrace();
      }
    }
  } 

  /**
   * 把配置文件先写到本地的一个文件中取
   *
   * @param ftpPath
   * @param str
   * @return
   */
  public boolean write(String fileName, String fileContext,
      String writeTempFielPath) {
    try {
      logger.info("开始写配置文件");
      File f = new File(writeTempFielPath + "/" + fileName);
      if(!f.exists()){
        if(!f.createNewFile()){
          logger.info("文件不存在，创建失败!");
        }
      }
      BufferedWriter bw = new BufferedWriter(new FileWriter(f, true));
      bw.write(fileContext.replaceAll("\n", "\r\n"));
      bw.flush();
      bw.close();
      return true;
    } catch (Exception e) {
      logger.error("写文件没有成功");
      e.printStackTrace();
      return false;
    }
  }
}

5.建立一个测试类FTPMain.java

package com.metarnet.ftp.main; 

import java.io.InputStream;
import java.util.Properties; 

import org.apache.log4j.Logger; 

import com.metarnet.ftp.read.ReadFTPFile;
import com.metarnet.ftp.util.FTPUtil;
import com.metarnet.ftp.write.WriteFTPFile; 

public class FTPMain { 

  private static Logger logger = Logger.getLogger(FTPMain.class); 

  public static void main(String[] args) {
    int ftpPort = 0;
    String ftpUserName = "";
    String ftpPassword = "";
    String ftpHost = "";
    String ftpPath = "";
    String writeTempFielPath = "";
    try {
      InputStream in = FTPUtil.class.getClassLoader()
          .getResourceAsStream("env.properties");
      if (in == null) {
        logger.info("配置文件env.properties读取失败");
      } else {
        Properties properties = new Properties();
        properties.load(in);
        ftpUserName = properties.getProperty("ftpUserName");
        ftpPassword = properties.getProperty("ftpPassword");
        ftpHost = properties.getProperty("ftpHost");
        ftpPort = Integer.valueOf(properties.getProperty("ftpPort"))
            .intValue();
        ftpPath = properties.getProperty("ftpPath");
        writeTempFielPath = properties.getProperty("writeTempFielPath"); 

        ReadFTPFile read = new ReadFTPFile();
        String result = read.readConfigFileForFTP(ftpUserName, ftpPassword, ftpPath, ftpHost, ftpPort, "huawei_220.248.192.200.cfg");
        System.out.println("读取配置文件结果为：" + result); 

        WriteFTPFile write = new WriteFTPFile();
        ftpPath = ftpPath + "/" + "huawei_220.248.192.200_new1.cfg";
        write.upload(ftpPath, ftpUserName, ftpPassword, ftpHost, ftpPort, result, writeTempFielPath);
      }
    } catch (Exception e) {
      e.printStackTrace();
    }
  }
} 

最后肯定是执行，看最后执行结果，OK步骤已讲完。

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持我们。