Member-only story

CORE JAVA INTERVIEW QUESTIONS AND ANSWERS

Gain Java Knowledge
28 min readSep 12, 2020

--

JAVA INTERVIEW QUESTIONS

1. Q : WHAT IS DATA HIDDING ?

ANS : Hiding of the data so that outside person can’t access our data directly.
By Using private modifier we can implement data hiding.
Ex :

class Account {
private double balance =1000;
}

The main advantage of Data Hiding is we can achieve security.

2. Q : WHAT IS DATA ABSTRACTION ?

ANS : Hiding internal implementation details & just highlight the set of services . What we are offering is called abstraction.
Ex :

Bank ATM Machine.

By using interfaces & abstract classes we can achieve abstraction.

The main advantage of abstraction are :

  • 1. We can achieve security as no one is allowed to known our internal implementation.
  • 2. Without effecting outside person we can change our internal implementation. Hence Enhancement will become very easy.

3.Q : WHAT IS ENCAPSULATION ?

ANS : Encapsulating data & corresponding methods into a single module is known as encapsulation.

If any java class follows Data Hiding and Abstraction such type of class is said to Encapsulated class.

Encapsulation = Data Hiding + Abstraction.

class Account {…

--

--

Gain Java Knowledge
Gain Java Knowledge

Written by Gain Java Knowledge

The Java programming language is one of the most popular languages today. Stay up to date with news, certifications, free learning resources and much more.

No responses yet