junit4-doc binary package in Ubuntu Lunar i386

 JUnit is a simple framework to write repeatable tests. It is an
 instance of the xUnit architecture for unit testing frameworks.
 .
 JUnit 4 uses Java 5 features such as generics and annotations. If
 you need compatibility with previous Java versions, you should use
 the junit package (version 3) instead.
 .
 This package contains Javadoc API documentation of JUnit 4.

Source package