Setting up JUnit with IntelliJ IDEA

Max picture Max · Oct 12, 2013 · Viewed 189.8k times · Source

Familiar with Java but unfamiliar with IntelliJ, how does one "get started" with JUnit integration?

Inspired by Looking for a tutorial on using JUnit with Intellij IDEA 9.x which didn't answer my questions and was for an older version of IntelliJ.

Answer

Max picture Max · Oct 12, 2013
  1. Create and setup a "tests" folder
    • In the Project sidebar on the left, right-click your project and do New > Directory. Name it "test" or whatever you like.
    • Right-click the folder and choose "Mark Directory As > Test Source Root".
  2. Adding JUnit library
    • Right-click your project and choose "Open Module Settings" or hit F4. (Alternatively, File > Project Structure, Ctrl-Alt-Shift-S is probably the "right" way to do this)
    • Go to the "Libraries" group, click the little green plus (look up), and choose "From Maven...".
    • Search for "junit" -- you're looking for something like "junit:junit:4.11".
    • Check whichever boxes you want (Sources, JavaDocs) then hit OK.
    • Keep hitting OK until you're back to the code.
  3. Write your first unit test

    • Right-click on your test folder, "New > Java Class", call it whatever, e.g. MyFirstTest.
    • Write a JUnit test -- here's mine:

      import org.junit.Assert;
      import org.junit.Test;
      
      public class MyFirstTest {
          @Test
          public void firstTest() {
              Assert.assertTrue(true);
          }
      }
      
  4. Run your tests
    • Right-click on your test folder and choose "Run 'All Tests'". Presto, testo.
    • To run again, you can either hit the green "Play"-style button that appeared in the new section that popped on the bottom of your window, or you can hit the green "Play"-style button in the top bar.