Java Algorithms Online Test

TestDome skill assessments are used by more than 3,700 companies and 450,000 individual test takers.

Jobseekers: Get a Certificate

Take a Practice Test

Companies: Try First, Pay Later

Sign Up To Use This Test
 Used by: 

The Java Algorithms online test assesses candidates' algorithmic-thinking skills and their ability to implement algorithms using Java.

It's an ideal test for pre-employment screening. A good developer will be able to design and implement algorithms that are both correct and efficient. Computational complexity is important not only when scaling applications but when creating responsive, maintainable, and efficient code.

This online test requires candidates to analyze or design an algorithm using Java as the programming language.

Recommended Job Roles

Java Developer
Back-End Developer
Web Developer

Sample Candidate Report


Sample Free Questions

Binary Search Tree

15min
  -  
Easy  
  -  
CODE

Java Algorithmic thinking Data structures Public

A three-node binary tree.Binary search tree (BST) is a binary tree where the value of each node is larger or equal to the values in all the nodes in that node's left subtree and is smaller than the values in all the nodes in that node's right subtree.

Write a function that, efficiently with respect to time used, checks if a given binary search tree contains a given value.

For example, for the following tree:

  • n1 (Value: 1, Left: null, Right: null)
  • n2 (Value: 2, Left: n1, Right: n3)
  • n3 (Value: 3, Left: null, Right: null)

Call to contains(n2, 3) should return true since a tree with root at n2 contains number 3.

Two Sum

30min
  -  
Easy  
  -  
CODE

Java Algorithmic thinking Searching Public

Write a function that, when passed a list and a target sum, returns, efficiently with respect to time used, two distinct zero-based indices of any two of the numbers, whose sum is equal to the target sum. If there are no two numbers, the function should return null.

For example, findTwoSum(new int[] { 3, 1, 5, 7, 5, 9 }, 10) should return a single dimensional array with two elements and contain any of the following pairs of indices:

  • 0 and 3 (or 3 and 0) as 3 + 7 = 10
  • 1 and 5 (or 5 and 1) as 1 + 9 = 10
  • 2 and 4 (or 4 and 2) as 5 + 5 = 10

Sorted Search

20min
  -  
Hard  
  -  
CODE

Java Algorithmic thinking Searching Public

Implement function countNumbers that accepts a sorted array of unique integers and, efficiently with respect to time used, counts the number of array elements that are less than the parameter lessThan.

For example, SortedSearch.countNumbers(new int[] { 1, 3, 5, 7 }, 4) should return 2 because there are two array elements less than 4.

Use Free Questions On a Trial Plan

Premium Questions

The premium question library contains our unique, hand-crafted questions. We offer a refund if you find any of them answered online.

Questions
Utilities, Runner, Document Store, Read Write Execute, Needle, Log Parser, Driver Exam, Crop Ratio, Programmer Teacher, Weighted Average, Chicken, Paragraph, Username, Chain Link, Hobbies, Read First Line, Node, Shipping, Racer, Stack to List, Snapshot, Date Transform, Segment, Shining Star, Test Results, Shelf, Internal Nodes, Document Counter, Moving Total, Entry, Unique Numbers, Rare, Remove Repetitions, Max Sum, Unique Name, Friend, Movie Night, Paper Strip, Stories, Train, Platformer, Product, Snow Storm
Skills
Java OOP Bug fixing Memory management Language Arithmetic Strings Stream Serialization Exceptions Data structures Arrays Iteration Multithreading Algorithmic thinking TDD Test case design Refactoring Searching Graphs Sorting Dynamic programming
Score Distribution
Loading...
Pricing For Premium Questions

Fully Customizable Tests

Add questions from our question library.
Create your own questions.
Customize test duration, number of questions, passing score, web proctoring, and more.
Create Free Account

Private Concierge

Send us an email with an explanation of your testing needs and a list of candidates. We will create an appropriate test, invite your candidates, review their results, and send you a detailed report.

What Others Say
TestDome user reviews on G2 Crowd
Simple, straight-forward technical testing

Testdome is simple, provides a reasonable (though not extensive) battery of tests to choose from, and doesn't take the candidate an inordinate amount of time. It also simulates working pressure with the time limits.

Jan Opperman, Grindrod Bank

Very smooth, well supported, great for assessing candidates

Very Prompt and helpful support when needed, we were looking to work with a third party to write and set up new tests, testdome was able to quickly set up and support a method to do this, allowing us to start testing candidates straight away.

George Offer, Guided Solutions

Easy to use and efficient for testing developers of different levels

It provides us an opportunity to set our own timing policy, to choose from variety of questions from different areas and with difficulty gradation. Also it is great that TestDome provides free of charge tests for candidates to prepare and check how online IDE works. And support is always ready to help:)

Alexandra Bulka, WorkFusion

On the TestDome Blog

Screening Applicants: The Good, the Bad and the Ugly

Since we’re all biased and we use incorrect proxies, why not just outsource hiring to experts or recruitment agencies? After all, they’ve been screening people for many years, so they must know how to do it right?

Not really. I was surprised to discover that many experts disagree with each other. Everybody praises their pet method and criticises the others. Many of these methods look legitimate, but are based on...

How TestDome Works

How TestDome Works

Want to know more? Check out our tour or contact us below.

Check Tour
or
Schedule a Demo

The TestDome Advantage

500+ premium, hand-crafted questions for 30+ job skills and 10+ coding languages.
Proctored tests, API access, and Applicant Tracking System (ATS) Integration.
Questions with small samples of actual work instead of academic problems.

Flexible Pricing

No monthly subscription or setup fee. No minimum contract period. You only pay for the candidates you test.

View Pricing