Java 实现ftp 文件上传、下载和删除详解编程语言

public class FtpUtils { 
//ftp服务器地址 
public String hostname = "192.168.1.249"; 
//ftp服务器端口号默认为21 
public Integer port = 21 ; 
//ftp登录账号 
public String username = "root"; 
//ftp登录密码 
public String password = "123"; 
public FTPClient ftpClient = null; 
/** 
* 初始化ftp服务器 
*/ 
public void initFtpClient() { 
ftpClient = new FTPClient(); 
ftpClient.setControlEncoding("utf-8"); 
try { 
System.out.println("connecting...ftp服务器:"+this.hostname+":"+this.port);  
ftpClient.connect(hostname, port); //连接ftp服务器 
ftpClient.login(username, password); //登录ftp服务器 
int replyCode = ftpClient.getReplyCode(); //是否成功登录服务器 
if(!FTPReply.isPositiveCompletion(replyCode)){ 
System.out.println("connect failed...ftp服务器:"+this.hostname+":"+this.port);  
} 
System.out.println("connect successfu...ftp服务器:"+this.hostname+":"+this.port);  
}catch (MalformedURLException e) {  
e.printStackTrace();  
}catch (IOException e) {  
e.printStackTrace();  
}  
} 
/** 
* 上传文件 
* @param pathname ftp服务保存地址 
* @param fileName 上传到ftp的文件名 
*  @param originfilename 待上传文件的名称（绝对地址） *  
* @return 
*/ 
public boolean uploadFile( String pathname, String fileName,String originfilename){ 
boolean flag = false; 
InputStream inputStream = null; 
try{ 
System.out.println("开始上传文件"); 
inputStream = new FileInputStream(new File(originfilename)); 
initFtpClient(); 
ftpClient.setFileType(ftpClient.BINARY_FILE_TYPE); 
CreateDirecroty(pathname); 
ftpClient.makeDirectory(pathname); 
ftpClient.changeWorkingDirectory(pathname); 
ftpClient.storeFile(fileName, inputStream); 
inputStream.close(); 
ftpClient.logout(); 
flag = true; 
System.out.println("上传文件成功"); 
}catch (Exception e) { 
System.out.println("上传文件失败"); 
e.printStackTrace(); 
}finally{ 
if(ftpClient.isConnected()){  
try{ 
ftpClient.disconnect(); 
}catch(IOException e){ 
e.printStackTrace(); 
} 
}  
if(null != inputStream){ 
try { 
inputStream.close(); 
} catch (IOException e) { 
e.printStackTrace(); 
}  
}  
} 
return true; 
} 
/** 
* 上传文件 
* @param pathname ftp服务保存地址 
* @param fileName 上传到ftp的文件名 
* @param inputStream 输入文件流  
* @return 
*/ 
public boolean uploadFile( String pathname, String fileName,InputStream inputStream){ 
boolean flag = false; 
try{ 
System.out.println("开始上传文件"); 
initFtpClient(); 
ftpClient.setFileType(ftpClient.BINARY_FILE_TYPE); 
CreateDirecroty(pathname); 
ftpClient.makeDirectory(pathname); 
ftpClient.changeWorkingDirectory(pathname); 
ftpClient.storeFile(fileName, inputStream); 
inputStream.close(); 
ftpClient.logout(); 
flag = true; 
System.out.println("上传文件成功"); 
}catch (Exception e) { 
System.out.println("上传文件失败"); 
e.printStackTrace(); 
}finally{ 
if(ftpClient.isConnected()){  
try{ 
ftpClient.disconnect(); 
}catch(IOException e){ 
e.printStackTrace(); 
} 
}  
if(null != inputStream){ 
try { 
inputStream.close(); 
} catch (IOException e) { 
e.printStackTrace(); 
}  
}  
} 
return true; 
} 
//改变目录路径 
public boolean changeWorkingDirectory(String directory) { 
boolean flag = true; 
try { 
flag = ftpClient.changeWorkingDirectory(directory); 
if (flag) { 
System.out.println("进入文件夹" + directory + " 成功！"); 
} else { 
System.out.println("进入文件夹" + directory + " 失败！开始创建文件夹"); 
} 
} catch (IOException ioe) { 
ioe.printStackTrace(); 
} 
return flag; 
} 
//创建多层目录文件，如果有ftp服务器已存在该文件，则不创建，如果无，则创建 
public boolean CreateDirecroty(String remote) throws IOException { 
boolean success = true; 
String directory = remote + "/"; 
// 如果远程目录不存在，则递归创建远程服务器目录 
if (!directory.equalsIgnoreCase("/") && !changeWorkingDirectory(new String(directory))) { 
int start = 0; 
int end = 0; 
if (directory.startsWith("/")) { 
start = 1; 
} else { 
start = 0; 
} 
end = directory.indexOf("/", start); 
String path = ""; 
String paths = ""; 
while (true) { 
String subDirectory = new String(remote.substring(start, end).getBytes("GBK"), "iso-8859-1"); 
path = path + "/" + subDirectory; 
if (!existFile(path)) { 
if (makeDirectory(subDirectory)) { 
changeWorkingDirectory(subDirectory); 
} else { 
System.out.println("创建目录[" + subDirectory + "]失败"); 
changeWorkingDirectory(subDirectory); 
} 
} else { 
changeWorkingDirectory(subDirectory); 
} 
paths = paths + "/" + subDirectory; 
start = end + 1; 
end = directory.indexOf("/", start); 
// 检查所有目录是否创建完毕 
if (end <= start) { 
break; 
} 
} 
} 
return success; 
} 
//判断ftp服务器文件是否存在     
public boolean existFile(String path) throws IOException { 
boolean flag = false; 
FTPFile[] ftpFileArr = ftpClient.listFiles(path); 
if (ftpFileArr.length > 0) { 
flag = true; 
} 
return flag; 
} 
//创建目录 
public boolean makeDirectory(String dir) { 
boolean flag = true; 
try { 
flag = ftpClient.makeDirectory(dir); 
if (flag) { 
System.out.println("创建文件夹" + dir + " 成功！"); 
} else { 
System.out.println("创建文件夹" + dir + " 失败！"); 
} 
} catch (Exception e) { 
e.printStackTrace(); 
} 
return flag; 
} 
/** * 下载文件 *  
* @param pathname FTP服务器文件目录 *  
* @param filename 文件名称 *  
* @param localpath 下载后的文件路径 *  
* @return */ 
public  boolean downloadFile(String pathname, String filename, String localpath){  
boolean flag = false;  
OutputStream os=null; 
try {  
System.out.println("开始下载文件"); 
initFtpClient(); 
//切换FTP目录  
                ftpClient.changeWorkingDirectory(pathname);  
FTPFile[] ftpFiles = ftpClient.listFiles();  
for(FTPFile file : ftpFiles){  
if(filename.equalsIgnoreCase(file.getName())){  
File localFile = new File(localpath + "/" + file.getName());  
os = new FileOutputStream(localFile);  
ftpClient.retrieveFile(file.getName(), os);  
os.close();  
}  
}  
ftpClient.logout();  
flag = true;  
System.out.println("下载文件成功"); 
} catch (Exception e) {  
System.out.println("下载文件失败"); 
e.printStackTrace();  
} finally{  
if(ftpClient.isConnected()){  
try{ 
ftpClient.disconnect(); 
}catch(IOException e){ 
e.printStackTrace(); 
} 
}  
if(null != os){ 
try { 
os.close(); 
} catch (IOException e) { 
e.printStackTrace(); 
}  
}  
}  
return flag;  
} 
/** * 删除文件 *  
* @param pathname FTP服务器保存目录 *  
* @param filename 要删除的文件名称 *  
* @return */  
public boolean deleteFile(String pathname, String filename){  
boolean flag = false;  
try {  
System.out.println("开始删除文件"); 
initFtpClient(); 
//切换FTP目录  
                ftpClient.changeWorkingDirectory(pathname);  
ftpClient.dele(filename);  
ftpClient.logout(); 
flag = true;  
System.out.println("删除文件成功"); 
} catch (Exception e) {  
System.out.println("删除文件失败"); 
e.printStackTrace();  
} finally { 
if(ftpClient.isConnected()){  
try{ 
ftpClient.disconnect(); 
}catch(IOException e){ 
e.printStackTrace(); 
} 
}  
} 
return flag;  
} 
public static void main(String[] args) { 
FtpUtils ftp =new FtpUtils();  
//ftp.uploadFile("ftpFile/data", "123.docx", "E://123.docx"); 
//ftp.downloadFile("ftpFile/data", "123.docx", "F://"); 
ftp.deleteFile("ftpFile/data", "123.docx"); 
System.out.println("ok"); 
} 
}