import org.jetbrains.annotations.NotNull; import org.jetbrains.annotations.Nullable; class Foo { @Nullable static Object foo() { return null; } static String bar(@NotNull Object arg) { return ""; } } class Bar { public static final String s = Foo.bar(<warning descr="Argument 'Foo.foo()' might be null">Foo.foo()</warning>); @NotNull public static Object o = <warning descr="Expression 'Foo.foo()' might evaluate to null but is assigned to a variable that is annotated with @NotNull">Foo.foo()</warning>; }