Junit test in IntelliJ IDE can't see class for testing

Question

I created simple Java project in IntelliJ, one class (RandomizedQueue) and generated JUnit test class for it. So it's just two files and they both are in the same directory - src.

Everything compiled and all was well. For some time. Then suddenly - it stopped with this error:

java: cannot find symbol
  symbol:   class RandomizedQueue
  location: class RandomizedQueueTest

I tried everything I could think of. Recreating a project worked for a while but the same error reappeared (without any obvious reason). I can't find any logic in this! Compilation from cmd does work.

I tried deleting everything from class and test - and I still can't make an instance in test method.

here is the whole project

Answer 1

See those white x-es next to the class name?

Somehow you have excluded RandomizedQueue class from the compilation.

Remove it from the excludes and everything will be back to where it was before.

PS: Coursera FTW :-)