Question 1

Why is the main() method declared static?

Accepted Answer

main() method is called by the JVM even before the instantiation of the class, hence it is declared as static

Question 2

What is the return type of the main() method?

Accepted Answer

Main() method doesn't return anything hence declared void

Question 3

What is the argument of main() method?

Accepted Answer

main() method accepts an array of String object as arguement

Question 4

Can a main() method be declared final?

Accepted Answer

Yes Any inheriting class will not be able to have it's own default main() method

Question 5

Does the order of public and static declaration matter in main() method?

Accepted Answer

No It doesn't matter but void should always come before main()

Question 6

Can a source file contain more than one class declaration?

Accepted Answer

Yes a single source file can contain any number of Class declarations but only one of the class can be declared as public

Question 7

Which package is imported by default?

Accepted Answer

javalang package is imported by default even without a package declaration

Question 8

Can a class be declared as protected?

Accepted Answer

A class can't be declared as protected only methods can be declared as protected

Question 9

What is the purpose of declaring a variable as final?

Accepted Answer

A final variable's value can't be changed final variables should be initialized before using them

Question 10

I do not want my class to be inherited by any other class. What should i do?

Accepted Answer

You should declared your class as final But you can't define your class as final, if it is an abstract class A class declared as final can't be extended by any other class

Question 11

When will you define a method as static?

Accepted Answer

When a method needs to be accessed even before the creation of the object of the class then we should declare the method as static

Question 12

How is final different from finally and finalize()?

Accepted Answer

final is a modifier which can be applied to a class or a method or a variable final class can't be inherited, final method can't be overridden and final variable can't be changed finally is an exception handling code section which gets executed whether an exception is raised or not by the try block code segment finalize() is a method of Object class which will be executed by the JVM just before garbage collecting object to give a final chance for resource releasing activity

Question 13

Which king class properly represents the relationship "King has a best friend who is a Soldier"?

Accepted Answer

class King { private Soldier bestFriend; }

Question 14

How many of the following will follow JavaBean Listener naming rules? addListener addMouseListener deleteMouseListener removeMouseListener registerMouseListener

Accepted Answer

2

Question 15

Keeping the actoins and attributes together under a single unit is called

Accepted Answer

Encapsulation is a process of binding the data objects together under a single unit.It is one ofthe elements of oops

Question 16

By whom will the unallocated memory that is no longer needed will be cleared in java?

Accepted Answer

The Java programming language provides a system-level thread to track memory allocation. Garbage collection has the following characteristics: • Checks for and frees memory no longer needed • Is done automatically • Can vary dramatically across JVM implementations

Question 17

What are the 3main tasks of JVM?

Accepted Answer

The JVM performs three main tasks: • Loads code • Verifies code • Executes code

Question 18

An algorithm written once which can be used in many places is called

Accepted Answer

Function is an algorithm which can be used any where in the program when required

Question 19

Client code having direct access to internal data is called

Accepted Answer

Client code must use setters and getters to access internal data in DataHiding

Question 20

There is one default constructor in every class.

Accepted Answer

There will always be a default constructor in every class

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