JAVA使用FTPClient类读写FTP

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。