Force method overriding

Question

Hi, my problem is the following: (basic sketch)
class A {
     public void y() { ... x(1, 5); ... }
     protected void x(int i, int j) { ... }
class B extends A {
     protected void x(int i, int j) { ... }
The meaning of which is that B is supposed to change part of y()'s behavior.
Now when in a project classes are modified all around, it may happen that someone changes the signature of A.x(), say to x(int i, int j, int k)
This immediately causes that calling B.y() produces no different behavior than calling A.y(), which is not intended.
So is there a way to force that B.x() must override a method in the base class? I would like to have it such that if A.x()'s signature changes and B.x()'s not, then a compile-time error occurs. (It makes sense if x() is some function with distinctive charasteristics, no overloaded forms, etc.)
Maybe it can be reached somehow with abstract methods?
Thanks,
Agoston

Answer 1

Something like this is what I've finally come up with:
Please note that I wasn't allowed to change the fact that B extends A for other reasons in the real application.
class A {
     protected interface I {
          void x(int i, int j);
     private static class AX implements I {
          public void x(int i, int j) { ... }
     private I getI() { return new AX(); }
     public void y() {
          I i = getI();
          i.x(1, 5);
class B extends A {
     private static class BX implements I {
          public void x(int i, int j) { ... }
     private I getI() { return new BX(); }
Requires a little additional work, but it's worth it so you don't have to check A if x()'s signature is still the same and B still does what you want, because whoever changes AX.x()'s signature, has to change I as well, and gets a compilation error if BX.x() isn't modified accordingly.