63 interview questions for developers (2026)

14 votes1666 runs0 comment

Eric Hostaleryat Dec 3, 2021

13 votes835 runs0 comment

Samuelat Mar 28, 2022

10 votes852 runs0 comment

Samuelat Mar 28, 2022

9 votes683 runs0 comment

design pattern

8 votes1546 runs0 comment

Eric Hostaleryat Dec 3, 2021

7 votes1620 runs0 comment

design pattern

Eric Hostaleryat Sep 19, 2022

7 votes834 runs0 comment

Samuelat Mar 28, 2022

5 votes1532 runs0 comment

Eric Hostaleryat Dec 3, 2021

5 votes1532 runs

Eric Hostaleryat Dec 3, 2021

5 votes1488 runs1 comment

5 votes803 runs1 comment

operator overloading

Samuelat Mar 28, 2022

4 votes1593 runs0 comment

Eric Hostaleryat Dec 3, 2021

4 votes1586 runs0 comment

Eric Hostaleryat Dec 3, 2021

4 votes1557 runs0 comment

Eric Hostaleryat Mar 13, 2023

4 votes642 runs0 comment

Samuelat Mar 28, 2022

3 votes1541 runs

Eric Hostaleryat Dec 3, 2021

3 votes1529 runs1 comment

Eric Hostaleryat Dec 3, 2021

3 votes750 runs2 comments

Samuelat Mar 28, 2022

3 votes686 runs

access modifiers

Samuelat Mar 28, 2022

3 votes666 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