Why is Intellij showing a cross (x) over the class

问题:

The icon that IntelliJ (v11.1) usually shows next to Java classes is a blue circle with a C. But for one of my classes this icon has a small "x" in the top left corner. This particular class is in a package with another class, which has just the usual C in a blue circle.

In case it matters, I'm using a Mac.

The class in question is AlertsHandler.

回答1:

This icon shows that the class is excluded from the compilation, it can be changed in Settings (Preferences on Mac) | Compiler | Excludes.