[Bluej-discuss] How to call an accessor method in a different class?

[Stephen Bloch]

>If ObjectA has an arraylist of ObjectB, and each ObjectB contains an
>instance of ObjectC which in turn contains an instance of ObjectD, and
>the class that defined ObjectD has an accessor method getName() . How do
>I call that method from within the class that defined ObjectA ?
>...
>Aryeh, thanks for the hint. There is no way that I would have guessed or
>stumbled on that particular syntax.

Aryeh is quite correct that this list isn't really intended for 
student questions about Java.  However, I want to comment on this.

One SHOULD be able to "guess or stumble upon" the syntax to do this, 
step by step.  How do you refer to ObjectA?  Next, how do you refer 
to its arraylist of ObjectB's?  Next, how do you refer to an 
individual one of those ObjectB's?  Next, how do you refer to the 
ObjectC in that ObjectB?  Next, how do you refer to the ObjectD in 
that ObjectC?  Next, how do you call getName on that ObjectD?  Each 
one of these questions should be easy to answer by itself, as long as 
you don't try to answer all six at once.

This might be a little easier if the first question or two had less 
magic in them -- in particular, the automatic "this" shortcut.  When 
I teach this stuff, I expect EVERY field reference to be of the form 
OBJECT.FIELDNAME, and EVERY method call to be of the form 
OBJECT.METHOD(ARGS); if the field or method is in the current object, 
my students are expected to use "this" explicitly as the OBJECT.
-- 
						Dr. Stephen Bloch
						Math/CS Department
						Adelphi University