use -source 7 or higher

Question

While trying to build a project using intelliJ Ultimate 12 I am getting these errors

use -source or higher to enable diamond operator
use -source 7 or higher         


        

Answer 1

For IntelliJ IDEA Community 2018.2:

• In the project tool window, right-click on the project name to get to the Project Structure menu.
• Set Language Level to whatever version you want, and rebuild project again.

You can also use F4 as shortcut to get to the same menu.