en Peris :
I am new in IntelliJ IDEA and I want to execute a single Junit test as I do in Eclipse but I haven't seen this option
GhostCat salutes Monica C. :
Intellij runs the unit test in context of your selection!
When you place the cursor on the class name, it will run the whole class. If you select a method name, only that method gets executed (upon turning to the menu or context menu).
You can also select a package in the project view and get to corresponding behavior.