Learn Java
Java Basics
Write real Java code in the browser, from your first output through conditions and loops to methods, classes and collections. Tests check your solution right away.
Start without an account
0 of 106 solved
Without an account you can try the first tasks. Your progress then stays in this browser.
Who is this course for?
For beginners with no prior knowledge, and for anyone refreshing Java for school, training, university or a job application.
What you will be able to do
- Write your own Java programs with variables, conditions, loops and methods
- Work with classes, objects, lists and collections
- Read error messages and secure programs with tests
12 chapters, 106 tasks
Each chapter builds on the previous one. Free and Pro chapters are marked.
Chapter 1 · Input and Output0/10 solved
Chapter 2 · Conditions0/10 solved
Chapter 3 · LoopsPro0/11 solved
- Lesson: Loops
- Rocket CountdownEasy
- Counting Without ThreesEasy
- Checkout Until ZeroEasy
- What Does It Print? i++ and ++iEasy
- Savings Goal with whileMedium
- Guess the Number with do-whileMedium
- Partial SumsMedium
- What Does It Print? Tracing LoopsMedium
- Find the Bug: Sum up to nMedium
- Star TriangleHard
- Primes up to nHard
Chapter 4 · ArraysPro0/11 solved
- Lesson: Arrays
- Look Up the WeekdayEasy
- Sum of an ArrayEasy
- Largest ValueEasy
- Times Table RowMedium
- Dice StatisticsMedium
- Reverse the RouteMedium
- What Does It Print? Arrays and ReferencesMedium
- What Does It Print? Loops over ArraysMedium
- Find the Bug: Counting Even NumbersMedium
- Book Cinema SeatsHard
- Tic-Tac-Toe WinnerHard