On this post, I will cover one of the new Java 9 features that attracted my attention: REPL. If you want to know what’s new on Java 9, you can visit this link. What is a REPL REPL stands for Read-Eval-Print-Loop. It’s a shell where the user can type an expression, it will be evaluated, and the result will be returned to the user. To me, the main purpose is to interact quickly with Java without creating a java file, compile it and run it.