Playground · Programming 
A real Java 21 sandbox in sixty seconds.
Java 21 with Maven. Compile, run, and bootstrap a Spring Boot service.
Open the Java 21 sandbox No account, no card, no install. Sixty minutes, extendable.
Playgrounds / Java 21Maven · Spring Boot60 min · extendable
What you can try
- Compile and run a class
- Create a Maven project
- Start a Spring Boot app and hit an endpoint
- Use streams and collections
No guided steps in a playground — it's yours to explore. When you want tasks and a verifier, the related labs below are the next step.
✓ sandbox allocated 0.4 s
✓ environment started
✓ terminal ready 38 s
You clicked Start. Sixty seconds later you're typing into something real.
Related labs
When you want tasks and a verifier.
The same Java 21 environment, with a sequence of checked tasks and a certificate at the end. All courses →
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