public class Test {
 public static void main(String[] args) {
   for (E e : E.values()) {
     e.m();
   }
 }
}

interface I {
 void m();
}

enum E implements I {
 X {
   public void m() {}
 }
}

This won't compile with one call to javac.
But if you separately compile I and E first you can then compile
Test just fine.