Re: backed or unbacked FlowSet

[Patrick LAM <plam@sable.mcgill.ca>]

On Sat, 27 Apr 2002, Florian Loitsch wrote:

> according to the javadoc of FlowSet the toList()-method returns an
> unbacked list. but the ArraySparseSet returns a backed list (again
> according to the javadoc).

Should return an unbacked list; you should be free to modify the list as
you wish without modifying the FlowSet, or make it a
Collections.unmodifiableList.  Either of those are unbacked.

> what is now the right implementation?
> could you give a good definition of "backed" and "unbacked"
> (dictionaries tend to forget these words...).

if you get a backed list and you modify the list, the change propagates to
the data structure which gave you the backed list.  For an unbacked list,
changes (if allowed) have no effect on the underlying data structure.

pat