NATIONAL OPEN UNIVERSITY OF NIGERIA

UNIVERSITY VILLAGE, PLOT 91, CASDASTRAL ZONE, NNAMDI AZIKIWE EXPRESS WAY, JABI, ABUJA.
FACULTY OF SCIENCES
APRIL/MAY 2019 EXAMINATION

COURSE CODE: CIT 383

COURSE TITLE: Introduction to Object-Oriented Programming

CREDIT: 2 Units

TIME ALLOWED: 2 Hours

INSTRUCTION: Answer Question ONE (1) and any other THREE (3) Questions

1a  Describe the activities of each of the following with respect to Object-Oriented programming

1. 1. Modularity
   2. Information.
   3. Code re-use
   4. Pluggability
   5. Class.
   6. Method.

(2 marks each)

b. Explain the for syntax as is used in Java programming (4 marks)

c. Describe the if construct as is used in Java programming. Use example (3marsk)

d. Explain any two commutative operations used in Java programming. (4 marks)

e. Describe the term, unary operator overloading (2 marks)

2a        Explain each of the following with respect to Object-oriented programming (OOP)

1. Encapsulation.
2. Inheritance.

(3 marks each)

2b        Discus each of the following with respect to Object-oriented programming

1. Reference variable of a class:  (3 marks)
2. Binding.(2 marks)

2c        Briefly discuss the two types of polymorphism (4 marks)

3a.       State any four advantages of using methods in Object oriented programming. (8 marks)

3b.       Using example, explain each of the following as each is used in Java programming (7 marks)

1. Predefined classes:

2. User defined classes.

4a.       Write a Java Program to print the message “ NOUN is a good school” and explain your codes. (5^1/₂ marks)

b.         Define:

1. Local variables (2 marks)
2. Instance variables (2 marks)

c.         Create a non-executable class that has a private instance variable that can hold the first name of a student. Your class should contain methods to assign values to and retrieve values from the instance variable. Explain your program. (5^1/₂ marks)

5a.       Enumerate and describe any four (4) motivations that exists using modularization. (4 marks)

b.         Explain the following:

1. Abstract classes (3^1/₂ marks)
2. Concrete classes (1^1/₂ marks)
3.  Abstract methods (3 marks)

c.         Outline the three kinds of modules that exist in Java programming. (3marks)