CareerCup

A basic file system can be shown as managmenet of data in Files & Folders. It should also manage the space available.

FIles and folder structure can be representd using Composite pattern as below:

class FileEntity
{
  // members common to File & Folder
  // create, copy, delete, move, getInfo, open, etc
};

class Folder : public FileEntity
{
  // a folder can have multiple FileEntity (folders or files)
  vector<FileEntity> m_VecFileEntity;
  // members of Folder
};

class File : public FileEntity
{
  // members of File
};

class Drive
{
  // members of Drive
  // getFreeSpace, getTotalSpace, createPartition, etc
};

class FileSystem
{
  vector<FileEntity> m_VecFileEntity;
  vector<Drive> m_vecDrives;
};

The two classes are
1. Folder
2. File

Now folder can have sub folders and files.

class Folder
{
ArrayList<Folder> subFolderList;
ArrayList<File> fileList;


Folder(File file)
{
fileList.add(file);
}
Folder(Folder folder)
{
subFolderList.add(folder);
}
Folder(Folder folder, File file)
{
folder.addFile(file);
subFolderList.addFolder(folder);
}

}

class File
{
String fileName;
MetaData metadata;

File(String fileName, MetaData metadata)
{
this.fileName = fileName;
this.metadata = metadata;
}


}

Composite pattern should be used here... Directory has files and 0 to many Directories in it again.
Directory and File can be identified by their properties.