Re: [Geotools-gt2-users] [Geotools-devel] Custom Filter Function - Getting Started Question

[Jody G. <jod...@gm...>]

I think I know what happened to you - however we should take the conversation to the user list. 

If your function did not reference any parameters, or if the parameters were literals, the SLD rendering engine has a chance to call your function once (rather than for each and every feature). This results in greater speed when rendering.

If your function is doing some processing of feature values, you will need to use a PropertyName expression to pass the values into your function. This allows your function to work in a range of situations, and indeed on non feature content such as a java util Map.

When rendering, the actual "feature" passed in only has non null content for the attributes referenced (as why request information you are not going to use?). One of the reasons GeoTools rendering is so fast is due to all these optimisations.
-- 
Jody Garnett


On Thursday, 11 July 2013 at 10:49 PM, lindsey wrote:

> In reality though I'm seeing that the method appears to only be called once
> (not once per record in data store) and that the feature parameter is always
> null. I've also noticed that the arguments are extracted with code like
> this:
>