Testing Java Swing components with Fest

entrada antigua del 28/3/2011 – old post from 3/28/2011


While exploring into new ways of writing automated unit test cases in Java, I discovered the Fest framework.

Besides some nice tools for mocking and wrapping calls to reflection, Fest has a convenient API to automate unit tests for Swing components leveraging the AWT Robot, which is too low-level as to be of real use for massive unit testing.

Of course, this is valid for integrated/assembly tests, not real unit tests, because Fest launches a Swing frame or dialog and then reproduces user gestures in the application (go to that field, enter that text, select that on the combo, press this button and so on). I find it useful because, especially in Swing, a thorough unit test suite is not enough to ensure proper user experience and bug-free deliveries. You need to test integrated, all the Swing widgets, event handlers and even business logic.

Results have been very good. Fest has some bugs but even with that I was able to write a good quantity of unit tests in a decent time. I will show some examples in this post.

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Using EasyMock to enable response text based testing of Java Servlets

entrada antigua del 23/3/2011 – old post from 3/23/2011


Behind this long title, today I would like to show an easy but powerful technique to unit test Java Servlets.

This method focuses in the fact that most of the Java Servlets are just returning plain text contents, usually HTML or XML.

For a proper unit test on the Java Servlet to run outside a web container, we need to mock the HttpServletRequest and HttpServletResponse objects. Mock, in short, is a term to refer to a double object, that is, an object that exists solely for the purpose of testing the unit at hand, with the same interface that an actual runtime object but with a different behavior, based on expectations.

It is not the purpose of this post to talk about mocks and other unit testing techniques. If you feel curious you can get more on the subject on this excellent paper from Martin Fowler (yes, ‘that’ Fowler guy): Mocks aren’t Stubs, by Martin Fowler.

With that being said, let’s go to the point. What we want to achieve is to test the output of a Java Servlet in different situations, asserting that this output contains certain strings of text. We will need to mock the request and response objects.

Continue reading “Using EasyMock to enable response text based testing of Java Servlets”

hola blog / hello blog

después de mucho tiempo dándole vueltas a la idea de crear un blog público (ya mantengo uno interno en el trabajo), al final me he decidido. un lugar donde contar cosas, supongo que principalmente sobre java y otras cosas que me gusten o me llamen la atención. un lugar donde dar cabida a pensamientos más largos de los que “caben” en facebook. el tiempo nos dirá a dónde llegamos.


after a long time thinking in creating a public blog (I already have one, internal at work), finally I have decided to do so. a place where to tell things, specially on java and others things that I like or simply caught my attention, I suppose. a place to put ideas and thoughts, longer than those that “fit” on facebook. only time will tell.