JAVA CONCEPTS

Important Java Mcq 1

Every Java application is composed of at least one?

a. Local variable

b. Instance variable

c. Public class declaration

d. Imported class

Answer:

c. Public class declaration

Explanation

In any Java program there must be a public class. As we know the program execution starts from the main method and the class of this main method is public. Although we don’t declare the class as public by default, it will be public only.

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