Reverse code problem


I have a question about the reverse code function. Have to classes like this (the sources are in JAVA):
class A {
private int x;

class B {
private float f;

When I make a new project and use “Tools/Code Engineering/JAVA Round-trip/Reverse code…” it creates the model perfectly. But after this I modify
the class A, and add “private B b;” line to it and try to reverse code again. Now the new variable is in the model (I can see it on the class diagram) but the association between class A and B is invisible. I do a right click on class A and choose “Related Elements/Show Associations” and now the association is also visible, everything is perfect.
After these I remove the added line from the source code, and do a “reverse code…” again. Now the variable is removed from class A but the association is still there, and I have to remove it by myself.

My question is that how could I do this automatically?

One more thing: If the class A contains the line “private B b;” at start, the first “reverse code…” creates perfect diagram. If I remove that line and do one more “reverse code…”, the diagram is still perfect (removes attribute and association too). If after these I do the same things as I wrote above it behaves the same…