64 interview questions for developers (2026)

14 votes1640 runs0 comment

Eric Hostaleryat Dec 3, 2021

13 votes809 runs0 comment

Samuelat Mar 28, 2022

10 votes827 runs0 comment

Samuelat Mar 28, 2022

9 votes657 runs0 comment

design pattern

8 votes1520 runs0 comment

Eric Hostaleryat Dec 3, 2021

7 votes810 runs0 comment

Samuelat Mar 28, 2022

6 votes1594 runs0 comment

design pattern

Eric Hostaleryat Sep 19, 2022

5 votes1506 runs0 comment

Eric Hostaleryat Dec 3, 2021

5 votes1506 runs

Eric Hostaleryat Dec 3, 2021

5 votes1463 runs1 comment

5 votes778 runs1 comment

operator overloading

Samuelat Mar 28, 2022

4 votes1560 runs0 comment

Eric Hostaleryat Dec 3, 2021

4 votes635 runs0 comment

Samuelat Mar 28, 2022

3 votes1557 runs0 comment

Eric Hostaleryat Dec 3, 2021

3 votes1531 runs0 comment

Eric Hostaleryat Mar 13, 2023

3 votes1515 runs

Eric Hostaleryat Dec 3, 2021

3 votes1503 runs1 comment

Eric Hostaleryat Dec 3, 2021

3 votes724 runs2 comments

Samuelat Mar 28, 2022

3 votes663 runs

access modifiers

Samuelat Mar 28, 2022

3 votes644 runs0 comment

Samuelat Mar 28, 2022

64 interview questionsfor developers (2026)

Test your developer skills before an interview with 64 corrected questions on 80+ topics. Beginner, Intermediate or Expert level.

64 interview questionsfor developers (2026)

Test your developer skills before an interview with 64 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?

Can a class implements several interfaces ?

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

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);

Explain the difference between overriding and overloading 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);

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

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