package files;

import java.util.Collection;
import java.util.Map;
import java.util.TreeMap;


public class Computer {

    Map dischi = new TreeMap();
    private char next = 'C';

    public void add(HardDisk hd) {
        hd.id = next;
        next ++;
        dischi.put(new Character(hd.id),hd);
    }

    public Collection elencoDischi() {
        return dischi.values();
    }

    public HardDisk getDisk(char c) {
        return (HardDisk)dischi.get(new Character(c));
    }
}
package files;


public class File {

    private long size;
    private String name;

    public File(String name, long size) {
        this.size = size;
        this.name = name;
    }

    public String getName() {
        return name;
    }

    public long getSize() {
        return size;
    }

    public String toString(){
        return name + " (" + size + ")";
    }
}
package files;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Comparator;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.StringTokenizer;
import java.util.TreeMap;


public class Folder {

    private Map folders = new TreeMap();
    private Map files = new TreeMap();
    private String name;
    private Folder father;

    public Folder(String name) {
        this.name = name;
    }

    public void addFolder(Folder folder)
            throws FolderAlreadyExisting {
        if(folders.get(folder.name)!=null){
            throw new FolderAlreadyExisting();
        }
        folders.put(folder.name,folder);
        folder.father = this;
    }

    public Object getFather() {
        return father;
    }

    public Folder getSubFolder(String name) {
//      return (Folder)folders.get(name);
        StringTokenizer st=new StringTokenizer(name,"/");
        return getFolder(st);
    }

    public void addFile(File file)
                throws FileAlreadyExisting {
        addFile(file,false);
    }

    public void addFile(File file, boolean forzaSostituzione)
                throws FileAlreadyExisting {
        if(!forzaSostituzione && files.get(file.getName())!=null){
            throw new FileAlreadyExisting();
        }
        files.put(file.getName(),file);
    }

    public Collection elencoAlfabeticoFile() {
        return files.values();
    }

    long getSize(){
        long size =5 * HardDisk.KB;
        Iterator it = folders.values().iterator();
        while(it.hasNext()){
            size += ((Folder)it.next()).getSize();
        }
        Iterator fit = files.values().iterator();
        while(fit.hasNext()){
            size += ((File)fit.next()).getSize();
        }
        return size;
    }

    public File getFile(String fileName) {
        return (File)files.get(fileName);
    }

    public Collection elencoSizeFile() {
        List lista = new ArrayList(files.values());
        Collections.sort(lista,
            new Comparator(){
                public int compare(Object o1,Object o2){
                    return (int)(((File)o1).getSize() - ((File)o2).getSize());
                }
            });
        return lista;
    }

    Folder getFolder(StringTokenizer st){
        if(!st.hasMoreTokens()){
            return this;
        }
        Folder f = (Folder)folders.get(st.nextToken());
        if(f!=null){
            return f.getFolder(st);
        }
        return null;
    }
}
package files;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Collection;

import javax.swing.*;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;




public class FsGui extends JFrame
implements ActionListener, ListSelectionListener {

  public static void main(String[] args){
    FsGui f = new FsGui();

  }

  public JButton btAddDisk;
  public JTextField diskSize;
  public JComboBox diskUnit;
  public JList diskList;

  public JTextField selDiskId;
  public JTextField selDiskAvailable;
  public JTextField selDiskSize;
  public JButton btFormat;

  Computer computer = new Computer();

  public FsGui(){
    super("File system");

    Container c = this.getContentPane();

    c.setLayout(new GridLayout(2,1));

    JPanel p1 = new JPanel();
    c.add(p1);
    //Container p1=c;

    p1.add(new JLabel("Size"));
    p1.add(diskSize = new JTextField(10));
    p1.add(diskUnit = new JComboBox(new String[]{"B","KB","MB","GB"}));
    p1.add(btAddDisk = new JButton("Add disk"));
    p1.add(new JScrollPane(diskList = new JList()));
    diskList.setVisibleRowCount(3);

    btAddDisk.addActionListener(this);
    diskList.addListSelectionListener(this);

    JPanel p2 = new JPanel();
    p2.add(new JLabel("Id:"));
    p2.add(selDiskId = new JTextField(3));
    p2.add(new JLabel("Size:"));
    p2.add(selDiskSize = new JTextField(15));
    p2.add(new JLabel("Avail:"));
    p2.add(selDiskAvailable = new JTextField(15));
    p2.add(btFormat = new JButton("Format"));
    c.add(p2);

    btFormat.addActionListener(this);

    this.setSize(600,300);
    this.setDefaultCloseOperation(DISPOSE_ON_CLOSE);
    this.setVisible(true);

  }

  public void actionPerformed(ActionEvent evt) {

    if(evt.getActionCommand().equals("Add disk")){
        System.out.println("Size:" + diskSize.getText() +
                        " " + diskUnit.getSelectedItem());

        String unit = (String) diskUnit.getSelectedItem();
        long multiplier=1;
        if(unit.equals("KB")) multiplier = HardDisk.KB;
        if(unit.equals("MB")) multiplier = HardDisk.MB;
        if(unit.equals("GB")) multiplier = HardDisk.GB;


        HardDisk hd = new HardDisk(Long.parseLong(diskSize.getText())*multiplier);


        computer.add(hd);
        updateDisks();
    }
    if(evt.getActionCommand().equals("Format")){
        HardDisk hd = (HardDisk)diskList.getSelectedValue();
        hd.format();
        valueChanged(null);
    }
  }

  private void updateDisks() {
    Collection disks = computer.elencoDischi();

    diskList.setListData(disks.toArray());
  }

  public void valueChanged(ListSelectionEvent evt) {
    HardDisk hd = (HardDisk)diskList.getSelectedValue();
    if(hd==null){
        selDiskId.setText("-");
        selDiskSize.setText("");
        selDiskAvailable.setText("");
    }else{
        selDiskId.setText(Character.toString(hd.getId()));
        selDiskSize.setText(""+hd.getSize());
        selDiskAvailable.setText(""+hd.getAvailable());
    }
  }



}package files;

import java.util.StringTokenizer;


public class HardDisk {
    public final static long KB=1024;
    public final static long MB=1024*KB;
    public final static long GB=1024*MB;

    private long size;
    char id;
    private Folder root;

    public HardDisk(long size) {
        this.size=size;
    }

    public char getId() {
        return id;
    }
    public long getSize() {
        return size;
    }
    public long getAvailable() {
        if(root!=null)
            return size-root.getSize();
        else
            return size;
    }
    public void format() {
        root = new Folder("");
    }

    public Folder getFolder(String path) {
//      StringTokenizer st=new StringTokenizer(path,"/");
//      Folder current = root;
//      while(st.hasMoreTokens()){
//          String element = st.nextToken();
//          current = current.getFolder(element);
//      }
//      return current;
// alternativa con la funzione ricorsiva
        return root.getSubFolder(path);
    }
    public File getFile(String path) {
        StringTokenizer st=new StringTokenizer(path,"/");
        Folder current = root;
        while(st.hasMoreTokens()){
            String element = st.nextToken();
            if(st.hasMoreTokens()){ // i.e. un folder
                current = current.getSubFolder(element);
            }else{
                return current.getFile(element);
            }
        }
        return null;
    }

    public String toString(){
        return id + ":";
    }
}