JAVA CONCEPTS

Important Java Mcq 1

Which of the following does not constitute the class’s relationship?

a. is-a

b. part-of

c. has-a

d. has-parts

Answer:

d. has-parts

Explanation

has-parts is the wrong answer! Object-oriented programming generally supports four types of relationships: inheritance , association, composition and aggregation. All these relationship is based on “is a” relationship, “has-a” relationship and “part-of” relationship.

Which keyword is used to import a package from the Java API library?

a) lib b) package c) getlib d) import Answer d) import

Which of the following is not a valid interface?

a. ResultSet b. DriverManager c. Statement d. Connection Answer: b. DriverManager Explanation: DriverManager is a class that acts as an interface between users and Drivers. It

All subclasses are a subtype in object-oriented programming.

a) True b) False Answer b) False Explanation: A subtype is something that is substituted for and behaves as its parent type. All subclass may

Which statement is true for object code?

i) It is used as its fundamental building block ii) Similar objects are classified using a concept of class iii) Polymorphism and abstraction are not