使用commons-net实现FTP文件上传与下载工具类

java使用commons-net包的FTPClient实现文件的上传下载工具类。

FTPUtil.java

package org.nercita.ltxx.testftp;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
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,int ftpPort,
String ftpUserName, String ftpPassword) {
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;
}

/**
* 本地上传文件到FTP服务器
* @param ftpPath 远程文件路径FTP
* @throws IOException
*/
public static 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, ftpPort,ftpUserName, ftpPassword);
// 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("上传文件失败!");
}
} 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 static boolean write(String fileName, String fileContext, String writeTempFielPath) {
try {
logger.info("写文件到本地缓存!");
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;
}
}

/**
* 从服务器的FTP路径下读取文件
* @param ftpUserName
* @param ftpPassword
* @param ftpPath
* @param FTPServer
* @return
*/
public static String readFileFromFTP(String ftpUserName, String ftpPassword,
String ftpPath, String ftpHost, int ftpPort, String fileName) {
StringBuffer resultBuffer = new StringBuffer();
InputStream in = null;
FTPClient ftpClient = null;
logger.info("开始从绝对路径：" + ftpPath + "读取文件!");
try {
ftpClient = FTPUtil.getFTPClient(ftpHost, ftpPort,ftpUserName, ftpPassword);
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();
} 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();

}
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();

}finally{
try {
ftpClient.disconnect();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return resultBuffer.toString();
}

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"));
ftpPath = properties.getProperty("ftpPath");
writeTempFielPath = properties.getProperty("writeTempFielPath");

String result = readFileFromFTP(ftpUserName, ftpPassword, ftpPath, ftpHost, ftpPort, "cfg.xml");
System.out.println("读取配置文件结果为：" + result);

ftpPath = ftpPath + "/" + "cfg_new.xml";
upload(ftpPath, ftpUserName, ftpPassword, ftpHost, ftpPort, result, writeTempFielPath);
}
} catch (Exception e) {
e.printStackTrace();
}
}

}