This is a cloud system that simulates the behaviour of DropBox, Google Drive or OneDrive. It is Java-based and it implements 4 design-patterns: Factory, Singleton, Observer and Composite.
Basically, the application it's based on a UNIX -like file system that allows all kind of operations, like: navigation (cd); creating / deleting files and folders (touch, rm, mkdir), printing information about files / folders, like creation date, size, ownership.
Also, there is implemented an user-management system that keeps tracking of login / logout operations made by any user and the entities created by them.
The application was created in Java SE 8, and the IDE used was IntelliJ IDEA 15.0.1.