/**
 * Class representing the file system.
 * 
 * @author Dpt. of Telematic Engineering, University Carlos III of Madrid
 * 
 */
public class FileSystem {

    /** File system (tree) root */
    private Folder root;

    /**
     * Constructor.
     */
    public FileSystem() {
        /* Contructor code */
    }// end constructor

    /**
     * Constructor.
     * 
     * @param rootFolderName
     *          Name of the root folder
     */
    public FileSystem(String rootFolderName) {
        /* Constructor code */
    }// end constructor

    /**
     * Search the folder specified as parameter in the file system, and return a
     * reference to the folder if it exists or null otherwise.
     * 
     * @param folderName
     *          Name of the folder to search.
     * @return a reference to the folder if it is in the file system, or null
     *         otherwise.
     */
    public Folder searchFolder(String folderName) {
        /* Searching code */
    }// end searchFolder

    /**
     * Add a new folder of the specified name, as a subdirectory of the folder
     * specified in the first parameter. If there exists a folder with name
     * newFolderName in the file system, or if parentFolderName does not exist,
     * the method does nothing and returns null. Otherwise it returns a reference
     * to the new folder.
     * 
     * @param parentFolderName
     *          Name of the parent folder.
     * @param newFolderName
     *          Name of the new folder.
     * @return a reference to the new folder, or null if there exists a folder
     *         with newFolderName in the file system of if the parent folder does
     *         not exist.
     */
    public Folder addNewFolder(String parentFolderName, String newFolderName) {
        /* Code to add a new folder */
    }// end addNewFolder

    /**
     * Print the file system structure in screen with the format: rootFolder
     * |_Folder1 |_Folder2 |_Folder3 |_Folder4 |_Folder5 |_Folder6 |_Folder7
     * |_Folder8
     */
    public void printFileSystem() {
        /* Code to print the file system */
    }// end printFileSystem
}