Assignment 3: hierarchy of Java classes

CIS 212 Assignment 3: 100 points
For this assignment, you will implement a hierarchy of Java classes that share a common
interface. You will then be able to create a data structure using this interface type and
populate it with various instances of classes inheriting from the interface.
1. [10] Implement a new interface named Measurable with a single method named getArea()
which takes no arguments and returns a double.
2. [10] Implement a new class named Rectangle that implements Measurable. Provide a class
constructor which takes arguments appropriate for creating a 2D rectangle and implement the
getArea() method to return the area of the rectangle.
3. [10] Implement a new class named Box that extends Rectangle. Provide a class constructor
which takes arguments appropriate for creating a 3D box and implement the getArea() method
to return the total surface area of the box.
4. [10] Implement a new class named Circle that implements Measurable. Provide a class
constructor which takes arguments appropriate for creating a 2D circle and implement the
getArea() method to return the area of the circle.
5. [10] Implement a new class named Sphere that extends Circle. Provide a class constructor
which takes arguments appropriate for creating a 3D sphere and implement the getArea()
method to return the surface area of the sphere.
6. [30] Implement a new class named Main with a public static main() method and private static
nextDouble() and calculateSum() methods:
• (10) The nextDouble () method should simply return a double on the range (0.0, 1.0)
(i.e., 0.0 and 1.0 exclusive) so that there are no 0.0 areas. Hint: see java.util.Random
nextDouble and java.lang.Double MIN_VALUE.
• (10) The calculateSum () method should take an ArrayList of type Measurable as an
argument and return the sum of all areas in the list.
• (10) The main() should create an ArrayList of type Measurable and populate that list
with 1000 random instances of your Measurable classes from parts 2-5 (i.e., 25% chance
of that each instance is one of the four classes). Use the nextDouble() method
described above to generate random dimensions to pass into the Measurable
constructors. Track the number of instances of each class created and print the results.
Finally call the calculateSum() method and print the result.
7. [20] Write code that is clear and efficient. Specifically, your code should be indented with
respect to code blocks, avoid unnecessarily repetitive code, avoid code that is commented out
or otherwise unused, use descriptive and consistent class/method/variable names, etc.
Your output should look something like:
rects: 244 boxes: 233 circles: 256 spheres: 267
sum: 1801.4553056918676
Please zip your Java source file(s), i.e., .java file(s), into a zipped file, rename that file as <Your
Full NameAssignment3.zip, e.g., BillGatesAssignment3.zip, and then upload that file to Canvas.
Do not put the Java source file(s) in a folder and zip that folder; instead, please directly select all
the Java source files and zip them altogether into a single zipped file.