That's an excellent observation, Nathan. Thanks for pointing this out.
Martin
On Tue, Nov 18, 2014 at 1:54 PM, Nathan Jensen <[email protected]> wrote:
> Hi,
>
> I've noticed in the newer versions of JTS that Geometry.equals(Object)
> calls into Geometry.equalsExact(other) which then goes into the subclasses
> to determine equality based on a tolerance. It appears that all identity
> checking has been removed from equals(Object) but you could speed up the
> check with a simple check for reference equality. Specifically, a one line
> change to Geometry.equalsExact(other) like this:
>
> public boolean equalsExact(Geometry other) {
> return this == other || equalsExact(other, 0);
> }
>
> will return quicker and save you the trouble of calculating equalsExact
> with the tolerance if you are comparing the exact same object in memory.
>
> This has performance implications beyonds just equals() calls. I traced
> this down while investigating Geotools'
> PolygonHandler.assignHolesToShells() because the
> ArrayList.indexOf(LinearRing) was slow and would compare the equalsExact
> even when it had the exact same object. This slight enhancement only saves
> time when you do encounter the exact same reference, but in those cases it
> can save a measurable amount of time.
>
> Please consider this slight optimization for a future release of JTS.
>
>
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