style question: length vs. size

[Harald Kirsch]

Vector has size().
Collection has size().
List has size().

StringBuffer has length().
String has length().
Arrays have length (the non-parentheses are not at issue here).

I am not sure if I see a consistent theme here. Is there
a theme? If I write a class to contain indexable elements,
along which guideline can I choose between length()
and size()?

Harald.

 

[Jacob]

Vector has size().
Collection has size().
List has size().

StringBuffer has length().
String has length().
Arrays have length (the non-parentheses are not at issue here).

I am not sure if I see a consistent theme here. Is there
a theme? If I write a class to contain indexable elements,
along which guideline can I choose between length()
and size()?

Use length() where the direction/order
of the elements has significance,
size() otherwise.

Of the above, only Collection qualify to
use size(). Vector and List use size()
because they inherit from Collection.
In my opinion Vector and List should
implement length() as a convenience
front-end to size().