java 中 FtpClient 实现 FTP 文件上传、下载

import java.io.BufferedWriter;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.FileWriter;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.net.SocketException;

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

import org.apache.commons.net.ftp.FTPFile;

import org.apache.commons.net.ftp.FTPReply;

import org.apache.log4j.Logger;

/**

* ftp 上传、下载工具类

* @author JiangYu

*/

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("请检查FTP的IP地址 ！ ");

} catch (IOException e) {

e.printStackTrace();

logger.info("请核对FTP的端口 ！ ");

}

return ftpClient;

}

/**

* 上传本地文件到FTP服务器

* @param ftpPath 服务器上存放文件的路径

* @param ftpUserName ftp服务账号

* @param ftpPassword ftp服务密码

* @param ftpHost ftp服务ip

* @param ftpPort ftp服务端口

* @param fileContent 文件内容

* @param writeTempFielPath 文件在本地的路径

*/

public static String upload(String ftpPath, String ftpUserName, String ftpPassword,

String ftpHost, int ftpPort, String fileContent, String writeTempFielPath) {

FTPClient ftpClient = null;

String uploadResult = "";

try {

ftpClient = 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);

}

// 先把文件写出到本地，再上传到FTP上，最后再删除 。

String result = write(remoteFileName, fileContent,

writeTempFielPath);

if (result.contains("成功")) {

File f = new File(writeTempFielPath + "/" + remoteFileName);

InputStream in = new FileInputStream(f);

ftpClient.storeFile(remoteFileName, in);

in.close();

uploadResult = "文件" + remoteFileName + "上传成功!";

f.delete(); // 删除本地临时文件

} else {

uploadResult = "文件" + remoteFileName + "上传失败!";

}

return uploadResult;

} catch (Exception e) {

e.printStackTrace();

return uploadResult+"错误源： "+e.getMessage();

}finally{

try {

ftpClient.disconnect();

} catch (IOException e) {

e.printStackTrace();

}

}

}

/**

* 文件写出到本地

* @param fileName 文件名

* @param fileContext 文件内容

* @param writeTempFielPath 本地存储路径

* @return

*/

public static String write(String fileName, String fileContext,

String writeTempFielPath) {

String result = "写出成功 !";

try {

File f = new File(writeTempFielPath + "/" + fileName);

if(!f.exists()){

if(!f.createNewFile()){

result = "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 result;

} catch (Exception e) {

result = "写出失败 ！";

e.printStackTrace();

return result;

}

}

/**

* 从FTP服务器下载文件

* @param ftpHost FTP服务器IP

* @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 String downFile(String ftpHost, int port,String username, String password,

String remotePath,String fileName,String localPath) {

String result = "下载失败 ！";

FTPClient ftp = new FTPClient();

try {

int reply;

ftp.connect(ftpHost, port);

ftp.login(username, password); // 登录

reply = ftp.getReplyCode();

if (!FTPReply.isPositiveCompletion(reply)) {

ftp.disconnect();

return "服务连接失败 ！";

}

ftp.changeWorkingDirectory(remotePath); // 转移到FTP服务器目录

FTPFile[] fs = ftp.listFiles();

boolean flag = false; // 下载文件不存在

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();

flag = true;

}

}

ftp.logout();

if(!flag){

result = "文件: "+fileName+"不存在 ！";

}else{

result = "下载成功 ！";

}

} catch (IOException e) {

e.printStackTrace();

} finally {

if (ftp.isConnected()) {

try {

ftp.disconnect();

} catch (IOException ioe) {}

}

}

return result;

}

}

import java.io.InputStream;

import java.util.Properties;

public class FtpTest {

public static void main(String[] args) {

new FtpTest().test();

}

private void test(){

int ftpPort = 0;

String ftpUserName = ""; // ftp服务账号

String ftpPassword = ""; // ftp服务密码

String ftpHost = ""; // ftp服务ip

String ftpPath = ""; // ftp服务器上存放文件的路径

String writeTempFielPath = ""; // 文件在本地的路径

String proName = "ftp.properties"; // 配置文件名

try {

// 配置文件一定要和本类放在同一包下才能找到

InputStream in = FtpUtil.class.getClassLoader().getResourceAsStream(proName);

if (in == null) {

throw new Exception("配置文件"+proName+"读取失败 ！");

}

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");

// 下载

String result = FtpUtil.downFile(ftpHost, ftpPort, ftpUserName, ftpPassword,

ftpPath, "JiangYu.csv", writeTempFielPath); // JiangYu.csv：下载文件的名称

System.out.println("文件下载结果为：" + result);

// 上传

ftpPath = ftpPath + "/" + "JiangYu.csv"; // JiangYu.csv：上传文件的名称

FtpUtil.upload(ftpPath, ftpUserName, ftpPassword, ftpHost, ftpPort, "这里是文件内容", writeTempFielPath);

} catch (Exception e) {

e.printStackTrace();

}

}