Where to add compiler options like -ea in IntelliJ IDEA?

I want to add the -ea option. I set it in Project Settings --> Compiler --> Java Compiler : Additional command line parameters.

But it caused a make error: invalid flag: -ea. P.S.: the above error message may not be the same as yours, because IntelliJ showed error in my native language, not English. I translated it into English.

Solution 1:

The -ea option to enable assertions is passed to the JVM not to the compiler. Add it as a VM option for your runtime configuration.

Specific location in the menu: Run > Edit Configurations... > Configuration > VM options:

Solution 2:

You can also make IntelliJ IDEA support assertions by default by changing the default Application configuration:

In the top menu, press Run > Edit Configurations > Defaults > Application > VM options.

To enable the assertion feature for all application, you could just fill the VM options with -ea

Solution 3:

For IntelliJ IDEA 2020.3:

• Run -> Edit Configurations... -> Modify options -> Add VM options.
• Input -ea then click OK button.