Is it acceptable to use exceptions instead of verbose null-checks?

Question

I recenly encountered this problem in a project: There\'s a chain of nested objects, e.g.: class A contains an instance variable of class B, which in turns has an instance v

Answer 1

It is bad design if parentObject needs to know that A contains a B which contains a C wich contains.... That way, everything is coupled to everything. You should have a look at the law of demeter: http://en.wikipedia.org/wiki/Law_Of_Demeter

parentObject should only call methods on its instance variable B. So, B should provide a method that allows for the decision, e.g.

public class A {
  private B myB;
  //...
  public boolean isItValidToDoSomething(){
    if(myB!=null){
      return myB.isItValidToDoSomething();
    }else{
      return false;
    }
  }
}

Eventually, at the level of Z, the method has to return true.

Imho, saving development time is never a reason for tolerating problems in the design. Sooner or later these problems will steal you more time than it would have taken to fix the problems in the first place