Download CSC113Lab5_2

King Saud University
College of Computer and Information Sciences
Department of Computer Sciences
CSC113: Computer Programming 2
Tutorial & Lab # 5: Abstract Classes,
Polymorphism and Interfaces
Exercise 1:
Table-1 presented mathematical operations classes. Hence the data and methods for each
class in the mathOp hierarchy UML class diagram (Figure-1) are illustrated in this table.
Instanceof
Table-1: Mathematical operations classes
Class
mathOp:
opName: String
Op1
Op2
+ toString()
+ result(): double
Addition:
+ Addition (double, double)
Subtraction:
+ Subtraction (double, double)
Multiplication:
+ Multiplication (double, double)
Division:
+ Division (double, double)
result()
toString()
Abstract
opName
Op1 + Op2
Op1 - Op2
Op1 * Op2
If Op2 != 0 result = Op1 / Op2
else result = -99999.99999
opName “: “
Op1 “ + ” Op2 “ = “ result()
opName “: “
Op1 “ - ” Op2 “ = “ result()
opName “: “
Op1 “ * ” Op2 “ = “ result()
If Op2 == 0 “Error: Divide by zero”
Else opName “: “ Op1 “ / ” Op2 “ = “ result()
{Abstract}
mathOp
Addition
Subtraction
Multiplication
Division
Figure-1: mathOp hierarchy UML class diagram
Implement the mathOp classes and then write the test class that has main() method as
follow:
1.
2.
3.
4.
Define four objects (one for each non-abstract class).
Define an array of mathOp consists of 4 objects.
Store the objects defined in step 1 into the array defined in step 2.
Print the array data except the objects of type Subtraction.
Exercise 2:
Implement the Shape hierarchy shown below. Each TwoDimensionalShape should contain
method getArea() to calculate the area of the two dimensional shape. Each
ThreeDimensionalShape should have methods getArea() and getVolume() to calculate the
surface area and volume, respectively.
1
Create a program that uses an array of Shape references to object of each concrete class in
the hierarchy. The program should print a text description of the object to which each array
element refers. Also, in the loop that processes all the shapes in the array, determine
whether each shape is a TwoDimensionalShape or ThreeDimensionalShape. If the shape is
TwoDimensionalShape, display its area. If a shape is a ThreeDimensionalShape, display
its area and volume.
Output
part of the main…
shapes[0]=
shapes[1]=
shapes[2]=
shapes[3]=
shapes[4]=
shapes[5]=
new
new
new
new
new
new
Circle(4);
Cube(2);
Sphere(3);
Square(7);
Circle(1);
Sphere(4);
Output should be like this:
This is a 2D shape.
Its area = 50.26548245743669
------------------This is a 3D shape.
Its area = 24.0
Its volume = 8.0
------------------This is a 3D shape.
Its area = 113.09733552923255
Its volume = 84.82300164692441
------------------This is a 2D shape.
Its area = 49.0
------------------This is a 2D shape.
Its area = 3.141592653589793
------------------This is a 3D shape.
Its area = 201.06192982974676
Its volume = 201.06192982974676
Exercise 3:
An airport charges any aeroplane lands in it by the following rules:
1. Every adult is charged 2 S.R. for every kilogram they weigh.
2. Every child is charged 0.5 S.R for every kilogram they weigh.
2
3. Every piece of luggage is charged 1.5 S.R. for every kilogram it weighs.
Every passenger has a name and a weight and every piece of luggage has an ID and weight.
Given the UML diagram of this problem, write a program that process one aeroplane and
display the information (name/ID, weight and charge) of the luggage or the passengers that
cost a charge of more than 50 S.R. Also, print the number of all adults, all children and all
pieces of luggage in that aeroplane.
While you are implementing your program, consider the following:
- Protect any method that is not intended to be overridden, from being overridden by
subclasses.
- Protect any concrete class from being inherited.
Hint: Represent an aeroplane as a collection (array) of Chargeable Objects.
Output
Part of the main…
chargeables[0]=
chargeables[1]=
chargeables[2]=
chargeables[3]=
chargeables[4]=
new
new
new
new
new
Child("Ahmed Ali",45.5);
Adult("Khalid Nasser",86.4);
Child("Noha Ameen",62);
Luggage(324,35.5);
Adult("Salem Saeed",94.25);
Output should be like this:
Name: Khalid Nasser
Weight: 86.4
Charge: 172.8
-------------ID: 324
Weight: 35.5
Charge: 53.25
-------------Name: Salem Saeed
Weight: 94.25
Charge: 188.5
-------------Number of adults = 2
Number of children = 2
Number of pieces of luggage = 1
--------------
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