Formatting: Each class must reside in its own file. If you need to instantiate objects of class A in your class B, your B.java file must import A.java first. The names you choose for your classes should match the ones specified in each problem. Also, for each problem i, you must have a Problem_i.java file containing (only) the class which has the main method. Finally, you must put all files related to problem i into a folder named problem_i. The files must be placed in the right sub-folder. Make sure that your code complies. See the note in Problem 1 for an example.
Submission: For each problem i submit one problem_i.zip file to Blackboard. The zip file should maintain the structure of the sub-folders. See the note in Problem 1 for an example.
Problem 1 [30pts]. Listed next is the skeleton for a class named Item. Each item has a name and unique ID number:
class Item {
private String name;
private int id;
}
Flesh out the class with appropriate accessors, constructors, and mutators. The id’s are unique and are assigned by your store and can be set from outside the Item class.
Next, modify the class so that it implements the Comparable interface. The class also
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overrides the compareTo method. This method imposes an order between instances of the Item class depending upon their ID. Test your class by creating an array of sample items and sort them in an ascending order using a sorting method that takes as input an array of type Comparable. You do not need to enforce uniqueness of IDs; that is, you can assume that IDs are unique.
Problem 2 [40pts]. Define an interface named Shape with a single method named area that calculates the area of the geometric shape:
public double area();
Next, define a class named Circle that implements Shape. The Circle class should have an instance variable for the radius, a constructor that sets the radius, accessor/ mutator methods for the radius, and an implementation of the area method. Also define a class named Rectangle that implements Shape. The Rectangle class should have instance variables for the height and width, a constructor that sets the height and width, accessor and mutator methods for the height and width, and an implementation of the area method. The following code should work with your code
public static void main(String[] args)
{
Circle c = new Circle(4); // Radius of 4
Rectangle r = new Rectangle(4,3); // Height = 4, Width = 3
ShowArea(c);
ShowArea(r);
}
public static void ShowArea(Shape s)
{
double area = s.area();
System.out.println("The area of the shape is " + area);
}
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