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Java Unit Testing in Java How to Test Assertions

10,358 Points

Why doesnt JUnit work with IntelliJs autoimport/import on the fly?

I noticed that when writing tests and using the test methods, I had to manually import things such as import static org.junit.Assert.*;. Usually, with auto-import on, I can write the method and have IntelliJ import it automatically. Why doesnt this seem to work with JUnit methods?

1 Answer

Good question orbyt! (I had the same thought..)

As it turns out (after doing a little research...)...

"The libraries for JUnit and TestNG are shipped with IntelliJ IDEA, but are not included in the classpath of your project or module by default. "

per this JetBrains page:


I know what you might be thinking:

"What! That's crazy!"

"Why aren't they included by default?"

"Are these people JetBrains or No Brains!?"

But I guess maybe it has something to do with giving the option for developers to set things up in their own custom way..

Personally I would definitely have appreciated a dialog/prompt at some point saying:

"You appear to be trying to use JUnit with IntelliJ -would you like to bring up a dialog to configure classpath now?"

(and of course I'm going to say yes and hope at least there's a little bit of auto-population in at least some of the fields in that dialog box that comes up...)

I might also recommend a quick read through of this page:


I'll also through in a few other links I found while researching (that might be helpful):



By the way there is mention of a "Fix" button at just past the 4:00 time point in the "Setting up a project for test" video, but this didn't work for me. I also didn't get an option for selecting JUnit4 in the list.

I ended up spending several hours reconstructing my whole IntelliJ setup to support the way Craig had was using it with JUnit (as opposed to the way I normally use IntelliJ, which is highly customized with my own plugins).

I really think Craig Dennis should have included this JetBrains TDD tutorial as a link in your teacher's notes:


By the way --here's the full list of Testing Frameworks that IntelliJ supports:

1.) JUnit 2.) TestNG 3.) Groovy JUnit 4.) FlexUnit 5.) PHPUnit 6.) MXUnit 7.) Cucumber

....that might also be useful for Craig Dennis to include as link (in the Teacher's Notes):


To anyone who ends up reading this forum thread I also might recommend trying out some of the Unit Testing plugins:


Of course Jetbrains has an OpenAPI, so you are free to develop your own IntelliJ plugins:




I am, of course, waiting (with bated breath) to see the JetBrains plug-in development course appear on the TeamTreehouse Roadmap any day now... :wink: