Question

用java写一个从linux上传下载的系统

一般使用ssh协议实现，需要图形界面操作，大家有这方面的资料吗。

Answer 1

可以用ftp实现文件的上传下载，跟linux还是windows没有关系。

把linux作为remote server就可以了。

public static void backupUploadWithCommonsFTP(File fileToBeUpload) {
FTPClient f = new FTPClient();
boolean backupDirectoryExist = false;
boolean fileToBeUploadExist = false;
FTPFile backupDirectory = null;
try {
f.connect(server.getServer());
f.login(server.getUsername(), server.getPassword());
FTPFile[] directories = f.listDirectories();
// Check for existence of backup directory
for (FTPFile file : directories) {
String filename = file.getName();
if (file.isDirectory() && filename.equalsIgnoreCase("backup")) {
backupDirectory = file;
backupDirectoryExist = true;
break;
}
}
if (!backupDirectoryExist) {
f.makeDirectory("backup");
}
// Check if file already exist on the server
f.changeWorkingDirectory("files");
FTPFile[] files = f.listFiles();
f.changeWorkingDirectory("backup");
String filePathToBeBackup="/home/user/backup/";
String prefix;
String suffix;
String fileNameToBeBackup;
FTPFile fileReadyForBackup = null;
f.setFileType(FTP.BINARY_FILE_TYPE);
f.setFileTransferMode(FTP.BINARY_FILE_TYPE);
for (FTPFile file : files) {
if (file.isFile() && file.getName().equals(fileToBeUpload.getName())) {
prefix = FilenameUtils.getBaseName(file.getName());
suffix = ".".concat(FilenameUtils.getExtension(file.getName()));
fileNameToBeBackup = prefix.concat(Calendar.getInstance().getTime().toString().concat(suffix));
filePathToBeBackup = filePathToBeBackup.concat(fileNameToBeBackup);
fileReadyForBackup = file;
fileToBeUploadExist = true;
break;
}
}
// If file already exist on the server create a backup from it otherwise just upload the file.
if(fileToBeUploadExist){
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
f.retrieveFile(fileReadyForBackup.getName(), outputStream);
InputStream is = new ByteArrayInputStream(outputStream.toByteArray());
if(f.storeUniqueFile(filePathToBeBackup, is)){
JOptionPane.showMessageDialog(null, "Backup succeeded.");
f.changeWorkingDirectory("files");
boolean reply = f.storeFile(fileToBeUpload.getName(), new FileInputStream(fileToBeUpload));
if(reply){
JOptionPane.showMessageDialog(null,"Upload succeeded.");
}else{
JOptionPane.showMessageDialog(null,"Upload failed after backup.");
}
}else{
JOptionPane.showMessageDialog(null,"Backup failed.");
}
}else{
f.changeWorkingDirectory("files");
f.setFileType(FTP.BINARY_FILE_TYPE);
f.enterLocalPassiveMode();
InputStream inputStream = new FileInputStream(fileToBeUpload);
ByteArrayInputStream in = new ByteArrayInputStream(FileUtils.readFileToByteArray(fileToBeUpload));
boolean reply = f.storeFile(fileToBeUpload.getName(), in);
System.out.println("Reply code for storing file to server: " + reply);
if(!f.completePendingCommand()) {
f.logout();
f.disconnect();
System.err.println("File transfer failed.");
System.exit(1);
}
if(reply){

JOptionPane.showMessageDialog(null,"File uploaded successfully without making backup." +
"\nReason: There wasn't any previous version of this file.");
}else{
JOptionPane.showMessageDialog(null,"Upload failed.");
}
}
//Logout and disconnect from server
in.close();
f.logout();
f.disconnect();
} catch (IOException e) {
e.printStackTrace();
}

}