63 interview questions for developers (2026)

14 votes1647 runs0 comment

Eric Hostaleryat Dec 3, 2021

13 votes815 runs0 comment

Samuelat Mar 28, 2022

10 votes833 runs0 comment

Samuelat Mar 28, 2022

9 votes664 runs0 comment

design pattern

8 votes1527 runs0 comment

Eric Hostaleryat Dec 3, 2021

7 votes1601 runs0 comment

design pattern

Eric Hostaleryat Sep 19, 2022

7 votes815 runs0 comment

Samuelat Mar 28, 2022

5 votes1513 runs0 comment

Eric Hostaleryat Dec 3, 2021

5 votes1513 runs

Eric Hostaleryat Dec 3, 2021

5 votes1470 runs1 comment

5 votes784 runs1 comment

operator overloading

Samuelat Mar 28, 2022

4 votes1571 runs0 comment

Eric Hostaleryat Dec 3, 2021

4 votes1567 runs0 comment

Eric Hostaleryat Dec 3, 2021

4 votes1538 runs0 comment

Eric Hostaleryat Mar 13, 2023

4 votes637 runs0 comment

Samuelat Mar 28, 2022

3 votes1522 runs

Eric Hostaleryat Dec 3, 2021

3 votes1510 runs1 comment

Eric Hostaleryat Dec 3, 2021

3 votes730 runs2 comments

Samuelat Mar 28, 2022

3 votes667 runs

access modifiers

Samuelat Mar 28, 2022

3 votes647 runs0 comment

Samuelat Mar 28, 2022

63 interview questionsfor developers (2026)

Test your developer skills before an interview with 63 corrected questions on 80+ topics. Beginner, Intermediate or Expert level.

63 interview questionsfor developers (2026)

Test your developer skills before an interview with 63 corrected questions on 80+ topics. Beginner, Intermediate or Expert level.

Is the following code valid? class Person { constructor(name, age) { this.name = name; this.age = age; } } const person = new Person('John', 20); console.log(person.name); console.log(person.age);

Overrided method visibility must be the same or less restrictive than the inherited method.

Inheritance in OOP.

You need to develop a class for which there should be only one instance throughout your application. Which design pattern should you use for this?

Can we extend an abstract class in Java?

Which design pattern allows to dynamically add responsibilities to an object?

Can a class implements several interfaces ?

Is the following code valid? class Person { constructor(name, age) { this.name = name; this.age = age; } } const person = new Person('John', 20); console.log(person.name); console.log(person.age);

Is the following code valid? class Person { constructor(name, age) { this.name = name; this.age = age; } } const person = new Person('John', 20); console.log(person.name); console.log(person.age);

Can an interface inherit from another interface?

When can you do a+b in OOP ?

Is the following code valid? class Person { constructor(name, age) { this.name = name; this.age = age; } } const person = new Person('John', 20); console.log(person.name); console.log(person.age);

Is the following code valid? class Person { constructor(name, age) { this.name = name; this.age = age; } } const person = new Person('John', 20); console.log(person.name); console.log(person.age);

Implement the interface IEmailFormatter for the classes Person, Company, and ListOfPerson, which has a method GetEmailContent()

Explain the difference between overriding and overloading in OOP.

What are the public methods of the class `Person`?

Implement the registration method on class A in a virtual way,Override the registration method on classes A1 and A2 when implementing these classes

Which modification of the following code WILL NOT make the output be "success" ?

What does the following code return ?

Overloading an operator in OOP