SAMPLE QUESTION PAPER

Object Oriented Programming using Java

SEMESTER 1& 2

Question 1 (25 marks)

a) Discuss the syntax, purpose and application, with an example for each, of the following:

i. if ii. while iii. for iv. switch (4 x 5 marks = 20 marks)

b) Write an independent Java method that accepts three sides of a triangle, say a, b and c and returns

“Equilateral” if all the three sides are equal, “Isosceles” if any two sides are equal “Scalene” otherwise. (5 marks)
Question 2 (25 marks)

a) Write an independent Java method that accepts an integer and returns true if it is a prime number, false otherwise. An integer is said to be prime if it is divisible by 1 and itself only. (9 marks)

b) Write an independent Java method that accepts an array of integers and returns the smallest of them. (8 marks)

c) Write a Java program to accept 10 integers and print the sum of numbers divisible by 5.
(8 marks)

Question 3 (25 marks)

a) Write a Java program to print the sum, average, maximum and minimum of 10 numbers. All numbers must be read from the user.
(8 marks)
b) What are formal and actual arguments? Explain with a sample program how they work in Java.
(8 marks)

c) Write a Java program to print first n Fibonacci sequence of numbers. The first two numbers of the sequence are 0 and 1; next number is the sum of the previous numbers.
(9 marks)

Question 4 (25 marks)

The assessments for the subject Object Oriented Programming consists of: • one assignment mark worth 30% of final assessment, plus • one examination mark work 70% of final assessment.

The subject instructor needs a program that accepts a student identification number and marks for the two assessments above as input, and determines and outputs the final mark and grade for each student. The grade awarded is based on the following scheme:

final mark letter grade less than 60 F greater than 60, less than 70 D greater than 70, less than 80 C greater than 80, less than 90 B greater than 90, less than or equal to 100 A

The assessment marks are of type integer, and student identification numbers are four-digit integers. The lecturer also wants the distribution of grades to be printed at the end.

Assume that the class KeyboardReader is available to you and use it to allow the user to enter the assessment mark. All results should be shown on the computer's screen.

Question 5 (25 marks)

This question requires you to implement and test a user-defined Java class. It requires similar work to that done with the sample classes covered in this subject

Objects of the class you are to create represent Appliance and, in general, Appliance objects are simulations of real appliances, which might be used by rental shops.

Analysis

The state of an Appliance object should include:

• Name ( a String) • Model ( a String) • Price (a double) The behavior of an Appliance object should include: • A method to initialise the Appliance objects with its Name, Model and price. • A reader method for each of the attributes. A reader method is a method that returns the value of the corresponding attribute. • A writer method for each of the attributes. The writer method for price should not allow the price to become negative. A writer method is a method that accepts a value as a parameter and sets the attribute value.
Design
Write the Appliance class in a file called Appliance. java and make sure that the class itself starts with:

class Appliance
{
Arguments must be used for any inputs to the Appliance writer methods. Any values output from the methods must be made available via a return value. Do not have any standard output (System.out.println) statements in any of the Appliance methods.
Question 6 (25 marks)

a) Write a simple applet with two buttons increase and decrease, and a text field. The default text field value will be 0. When a user clicks increase, the value in the text field increases by 1. When the user clicks decrease, the value is decreased by 1.
(12 marks)

b) Write a Java program, which defines an array of 10 elements and reads real numbers from the user. Write a separate method to print the output in ascending order. (13 marks)