AssertJ Swing is a Java library that provides a fluent interface for functional Swing UI testing. page 
AssertJ Swing is based on JDK standard types assertions and can be used with either JUnit or TestNG.
Different AssertJ Swing major versions depend on different Java versions:
* AssertJ Swing 3.x requires Java 8 or higher * AssertJ Swing 2.x requires Java 7 or higher * AssertJ Swing 1.x requires Java 6 or higher