java操作FTP还是很方便的，有多种开源支持，这里在apache开源的基础上自己进行了一些设计，使用起来更顺手和快捷。
思路：
1.设计FTPHandler接口，可以对ftp，sftp进行统一操作，比如上传，下载，删除，获取关闭连接等
2.对FTP和SFTP的实现
3.设计一个工厂（考虑以后可能有sftp，ftp两种，目前只实现一种FTP的），用来生成FTPHandler
4.简单使用说明
作为码农，上代码更实在。
接口 FTPHandler.java
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.SocketException; import org.apache.commons.net.ftp.FTPClient; public interface FTPHandler {
/**
* 获取连接
* @return
* @throws SocketException
* @throws IOException
*/
public boolean connect() throws SocketException, IOException;
/**
* 上传文件
* @param remotePath 要保存到的远程ftp目录
* @param originalFilename 要保存为远程ftp文件名
* @param is 输入流
* @return
*/
public boolean uploadFile(String remotePath,String originalFilename, InputStream is); /**
* 下载文件
* @param remotePath 文件所在的远程ftp目录
* @param filename 文件名
* @param os 输出流
* @return
* @throws IOException
*/
public boolean downFile(String remotePath,String filename, OutputStream os) throws IOException; /**
* 删除文件
* @param remotePath 文件所在ftp目录
* @param filename 文件名
* @return
* @throws IOException
*/
boolean deleteFiles(String remotePath,String filename) throws IOException; /**
* 关闭客户端
* @param ftpClient
*/
public void closeClient(FTPClient ftpClient); }
实现类 FTPHandlerImpl.java
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.SocketException;
import java.util.Properties; import org.apache.commons.lang.StringUtils;
import org.apache.commons.net.ftp.FTP;
import org.apache.commons.net.ftp.FTPClient;
import org.apache.commons.net.ftp.FTPFile;
import org.apache.commons.net.ftp.FTPReply;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory; public class FTPHandlerImpl implements FTPHandler { private static final Logger LOGGER= LoggerFactory.getLogger(FTPHandlerImpl.class); private static String url="";
private static int port=21;
private static String username=null;
private static String password=null;
private static String remotePath=null;
private FTPClient ftpClient = null; static {
Properties configP;
try {
configP = PropertiesUtils.getWebLoProperties("configure");
url = configP.getProperty("downFileService.ftp.url");
username = configP.getProperty("downFileService.ftp.username");
password = configP.getProperty("downFileService.ftp.password");
remotePath = configP.getProperty("downFileService.ftp.remotePath");
// localPath = configP.getProperty("downFileService.ftp.localPath");
} catch (Exception e) {
e.printStackTrace();
}
} public FTPHandlerImpl() {
FTPClient ftpClient = new FTPClient();
this.ftpClient=ftpClient;
} @Override
public boolean connect() throws SocketException, IOException {
boolean success=true;
ftpClient.connect(url, port);
boolean login = ftpClient.login(username, password);
int replyCode = ftpClient.getReplyCode();
if (!FTPReply.isPositiveCompletion(replyCode)) {
success=false;
}
return success&&login; } @Override
public boolean uploadFile(String _remotePath,String storeFilename, InputStream is) {
boolean success=false;
try {
// 切换到path指定的目录
if(StringUtils.isBlank(_remotePath)){
_remotePath=remotePath;
} createOrChangeDir(_remotePath);
ftpClient.setFileType(FTP.BINARY_FILE_TYPE);
ftpClient.setFileTransferMode(FTP.BINARY_FILE_TYPE);
success = ftpClient.storeFile(storeFilename, is);
is.close();
} catch (IOException e) {
e.printStackTrace(); }
closeClient(ftpClient);
return success;
} @Override
public boolean downFile(String _remotePath,String filename, OutputStream os) throws IOException {
// 解决图片上传失真
//解决图片下载失真
// 切换到path指定的目录
if(StringUtils.isBlank(_remotePath)){
_remotePath=remotePath;
}
createOrChangeDir(_remotePath);
ftpClient.setFileType(FTP.BINARY_FILE_TYPE);
ftpClient.setFileTransferMode(FTP.BINARY_FILE_TYPE);
FTPFile[] ftpFiles = ftpClient.listFiles();
boolean success=false;
for (FTPFile file : ftpFiles) {
if (file.getName().equals(filename)) {
filename = file.getName();
success = ftpClient.retrieveFile(filename, os);
break;
}
}
closeClient(ftpClient);
return success;
} @Override
public boolean deleteFiles(String _remotePath,String fileName) throws IOException {
// 切换到path指定的目录
if(StringUtils.isBlank(_remotePath)){
_remotePath=remotePath;
}
ftpClient.changeWorkingDirectory(_remotePath);
FTPFile[] ftpFiles = ftpClient.listFiles();
boolean isDelete = false;
for (FTPFile file : ftpFiles) {
if (fileName.equalsIgnoreCase(file.getName())) {
ftpClient.deleteFile(file.getName());
isDelete = true;
} }
closeClient(ftpClient);
return isDelete;
} @Override
public void closeClient(FTPClient ftpClient) {
try {
if (ftpClient != null) {
ftpClient.logout();
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (ftpClient != null && ftpClient.isConnected()) {
try {
ftpClient.disconnect();
} catch (IOException ioe) {
ioe.printStackTrace();
}
}
} } /**
* 创建目录(有则切换目录，没有则创建目录)
* @param dir
* @return
*/
private boolean createOrChangeDir(String dir){
if(StringUtils.isBlank(dir))
return true;
String d;
try {
//目录编码，解决中文路径问题
d = new String(dir.toString().getBytes("UTF-8"),"iso-8859-1");
//尝试切入目录
if(ftpClient.changeWorkingDirectory(d))
return true; dir = StringUtils.removeStart(dir, "/");
dir = StringUtils.removeEnd(dir, "/");
String[] arr = dir.split("/");
StringBuffer sbfDir=new StringBuffer();
//循环生成子目录
for(String s : arr){
sbfDir.append("/");
sbfDir.append(s);
//目录编码，解决中文路径问题
d = new String(sbfDir.toString().getBytes("UTF-8"),"iso-8859-1");
//尝试切入目录
if(ftpClient.changeWorkingDirectory(d))
continue;
if(!ftpClient.makeDirectory(d)){
LOGGER.info("[失败]ftp创建目录："+sbfDir.toString());
return false;
}
LOGGER.info("[成功]创建ftp目录："+sbfDir.toString());
}
//将目录切换至指定路径
return ftpClient.changeWorkingDirectory(d);
} catch (Exception e) {
e.printStackTrace();
return false;
}
} }
工场类 FTPFactory.java
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.SocketException;
public class FTPFactory { public static final String HANDLE_FTP="ftp";
public static final String HANDLE_SFTP="sftp"; /**
* 获取FTPHandler对象，目前只实现了ftp
* @param handleName HANDLE_FTP或HANDLE_SFTP
* @return
*/
public static FTPHandler getHandler(String handleName){
FTPHandler handler=null;
if(handleName.equals(HANDLE_FTP)){
handler=new FTPHandlerImpl();
}
return handler;
} public static void main(String[] args) throws SocketException, IOException {
FTPHandler handler = getHandler(HANDLE_FTP);
boolean connect = handler.connect();
if(connect){
File f=new File("C:\\Users\\pcdalao\\Desktop\\definitions.json");
InputStream is=new FileInputStream(f);
boolean uploadFile = handler.uploadFile("/upload_case/20170825/测试", "definition_test.json", is);
if(uploadFile){
System.out.println("success");
}else{ System.out.println("fail");
} } } }
使用的时候，直接从工程获取即可。
说明：PropertiesUtils这个工具类，有很多可以替代的实现，需要自己实现哦。
就此一个完整的FTP操作完成。记录一下，方便自己，也方便园子里的朋友参考。设计不当之处，请多多指教。