JUnit is a unit testing framework for Java. There are numerous XUnit implementations where X is replaced by a suitable name for the language. JUnit supports the rapid, and in some cases automatic, development of unit tests. JUnit has been used for years as a standalone product. It is available as a plug-in for the Eclipse development environment.

JUnit is primarily used by software developers responsible for creating components and delivering them into the core asset base. 

The figure shows the JUnit interface in Eclipse. The green bar in the lower right of the screen indictaes that all of the tests that were just run were successful. Just to the left of that bar is the same information given numerically. Tutorials are available for JUnit ay junit.org.