Job offersCompaniesTestsBlogI'm an employerSign upLog in
fr
fr
Home>IT Tests>Questions>Java

145 interview questions on Javafor developers (2024)

Test your technical skills before an interview of Java with 145 corrected questions. Beginner, Intermediate or Expert level.

or
Technology
Profession
Sort by
Newest
Most popular
Last review
Filter by
Published
145
To review
0
145 questions
Easy
15 votes1691 runs3 comments

Write a Java program that prints 'welovedev'.

Full stack developer
strings
variables
Pierreat Sep 19, 2022
Hard
8 votes2591 runs0 comment

A Customer class has the com.company.model package.

Back-end developer
inheritance
package
Thomas De verdièreat Jan 4, 2022
Hard
8 votes2554 runs0 comment

How many times is the condition `(a++ < 15)` evaluated in the following code? ```java int a = 3; while (a++ < 15) { if ((a++ % 5) == 0) break; } ```

Back-end developer
loops
control flow
Thomas De verdièreat Dec 16, 2021
Easy
8 votes1650 runs0 comment

How should a package be named in Java?

Full stack developer
packages
java
Pierreat Sep 19, 2022
Hard
7 votes2492 runs0 comment

A monitor in Java

Back-end developer
java
thread
Thomas De verdièreat Jan 4, 2022
Hard
6 votes2533 runs1 comment

How to write a portable Java program

Back-end developer
java
native
Thomas De verdièreat Jan 4, 2022
Hard
6 votes2513 runs0 comment

Write a finalizer in Java.

Back-end developer
java
finalizer
Thomas De verdièreat Dec 16, 2021
Medium
5 votes2536 runs0 comment

What does the final keyword mean in front of a method in Java?

Back-end developer
java
methods
Thomas De verdièreat Jan 4, 2022
Easy
5 votes2499 runs0 comment

What are the visibility modifiers for a method in Java?

Back-end developer
access modifiers
methods
Thomas De verdièreat Jan 4, 2022
Hard
5 votes2486 runs0 comment

What "design pattern" makes it possible to offer a means of treating the elements of a tree without worrying about the course?

Back-end developer
design pattern
tree
Thomas De verdièreat Jan 4, 2022
Easy
5 votes2476 runs0 comment

Which of these classes is the most suitable for composing a character string from several elements concatenated to each other?

Back-end developer
string
java
Thomas De verdièreat Jan 4, 2022
Hard
5 votes2434 runs0 comment

How many instance of Integer cannot be freed from memory?

Back-end developer
array
memory
Thomas De verdièreat Dec 16, 2021
Easy
5 votes1615 runs1 comment

How to concatenate two strings of characters in Java?

Full stack developer
strings
concatenation
Pierreat Jan 4, 2022
Hard
4 votes2542 runs0 comment

A “synchronized” method

Back-end developer
java
method
Thomas De verdièreat Jan 4, 2022
Hard
4 votes2530 runs1 comment

Serialization can be customized with the Externalizable interface

Back-end developer
serialization
interface
Thomas De verdièreat Jan 4, 2022
Easy
4 votes2498 runs0 comment

What is the classpath for?

Back-end developer
java
classpath
Thomas De verdièreat Jan 4, 2022
Hard
4 votes2495 runs1 comment

A referenced object is an object that can be reached by a “living” thread.

Back-end developer
java
garbage collection
Thomas De verdièreat Jan 4, 2022
Hard
4 votes2460 runs0 comment

What design pattern will you use to dynamically add capabilities to an object in Java?

Back-end developer
design patterns
object
Thomas De verdièreat Jan 4, 2022
Hard
4 votes279 runs1 comment

The Garbage Collector G1(or Garbage First) is a GC that organizes the heap in a way

Back-end developer
garbage collection
java
Loïcat Jan 31, 2022
Hard
3 votes2511 runs0 comment

What is the error message when you try to serialize a class that does not implement Serializable?

Back-end developer
java
serialization
Thomas De verdièreat Dec 2, 2021
Java tests