http://www.uispec4j.org/

UISpec4J is an Open Source functional and/or unit testing library for Swing-based Java applications, built on top of JUnit  and TestNG.

If you are writing a Swing application, you will appreciate UISpec4J above all
for its simplicity: UISpec4J's APIs are designed to hide as much as possible the complexity
of Swing, resulting in easy to write and easy to read test scripts. This is especially true when comparing
UISpec4J tests with those produced using Swing or low-level, event-based testing
libraries.

Here is for example how a JTable content is tested with UISpec4J:

public void testContacts() { Table contacts = getMainWindow().getTable(); assertTrue(contacts.contentEquals(new Object[][]{ {"John", "12", Boolean.FALSE}, {"Sylvia", "43", Boolean.TRUE}, {"Bill", "31", Boolean.FALSE}})); }

This code is shorter than what would be needed using the Swing APIs, but there is more:
it checks the values actually
displayed
by the underlying JTable component, not just its
internal model values. Achieving this with Swing would require checking the values computed by the
renderers, resulting in several times as many lines of code.