Oddity in ModuleClassLoader.isModulePresent

[Jesse Glick]

In java.lang.module.ModuleClassLoader:

     public boolean isModulePresent(String mn) {
         return ((org.openjdk.jigsaw.Loader)this).isModulePresent(mn);
     }

And in org.openjdk.jigsaw.Loader this method is indeed overridden.

Would it not be more straightforward to just mark isModulePresent abstract?