• creation: that, given an integer n, creates a Wardrobe object with n hooks that initially are all empty;
• getNumHooks: that returns the number of hooks of the wardrobe;
• assignHook: that, given the code c of an item (a string), occupies the first empty hook (i.e., the empty hook with the smallest number) with the item c and returns the number of the hook, if there is an empty hook; if there is no empty hook, then -1 is returned and the wardrobe is not modified;
• emptyHook: that, given the number n of a hook, makes hook n empty;
• getItem: that, given the number n of a hook, returns the code of the item currently occupying hook n, if the hook is occupied; null otherwise;
• searchItem: that, given the code c of an item, returns the number of the hook occupied by the item c, if it exists; -1 otherwise;
• getNumOccupiedHooks: that returns the number of occupied hooks in the wardrobe;
• reorderWardrobe: that rearranges the items in the wardrobe in such a way that all hooks up to a certain number are occupied, and the remaining ones are all free.

Part 1. Write a Java class Wardrobe to represent Wardrobe objects.

Solution: representation of the objects, skeleton of the class, class Wardrobe

Alternative solution: representation of the objects, skeleton of the class, class Wardrobe2

Part 2. Realize a static method saveItemAssignment, client of the class Wardrobe that, given a wardrobe g, writes on standard output, one per line, the number of the hook and the code of the item that occupies it, for all occupied hooks in the wardrobe g.

Solution

Alternative solution

Part 3. Describe how memory is managed when methods are activated and when their activation terminates. Specifically, describe when local variables and formal parameters are created and destroyed, and when and how they are initialized. Illustrate the concepts you explain on the following example:

public class Example {
  public static double m(int p) {
    double d;
    d = p / 2.0;
    return d;
  }
  public static void main (String[] args) {
    int a = 5, b = 4;
    double r;
    r = m(a + b);
    System.out.println(r);
  }
}