Re: Modifying data models within the template

I implemented my own ObjectWrapper and that seems to work.

Question #1 is still open, though. Does anyone know if modifying a data 
model during template processing will lead to threading problems?




On 7/7/2011 4:29 PM, Chris wrote:
> A bit of poking around shows that the default ObjectWrapper wraps Maps
> in a SimpleHash, and the SimpleHash copies the map. That's the answer to
> question #2. Is there an easy way to get it to stop doing this?
>
> Making a copy of every hash in the system strikes me as an unnecessary
> performance killer.
>
>
>
>
> On 7/7/2011 4:18 PM, Chris wrote:
>> We need to give [#includes] and subpages their own datamodels to keep
>> things modular. The scheme I've come up with is to create a directive
>> that can be included at the top of each template that will add that
>> template's data to the top-level data model.
>>
>> Two questions:
>>
>> 1. This is an explicit violation of the "data models are read-only" rule
>> described here:
>>
>> http://freemarker.sourceforge.net/docs/pgui_misc_multithreading.html
>>
>> If a new datamodel is created for each page fetch, is this a problem?
>> I'm running in a servlet environment. So far as I can tell, only the
>> thread that is processing the page will ever see this data model.
>>
>> 2. When I use a HashMap as the main "root" data model, the scheme fails.
>> The template says that the variables I've added to the model do not
>> exist. The scheme *works* when I have the root HashMap point to an
>> object, and then I replace the value of that object. There's something
>> about adding a new key to the HashMap during template processing that
>> the system doesn't like.
>>
>> Is the template processing code playing games with my HashMap, like
>> making a copy? Why?
>>
>>
>> ------------------------------------------------------------------------------
>> All of the data generated in your IT infrastructure is seriously valuable.
>> Why? It contains a definitive record of application performance, security
>> threats, fraudulent activity, and more. Splunk takes this data and makes
>> sense of it. IT sense. And common sense.
>> http://p.sf.net/sfu/splunk-d2d-c2
>
>
>
> ------------------------------------------------------------------------------
> All of the data generated in your IT infrastructure is seriously valuable.
> Why? It contains a definitive record of application performance, security
> threats, fraudulent activity, and more. Splunk takes this data and makes
> sense of it. IT sense. And common sense.
> http://p.sf.net/sfu/splunk-d2d-c2



------------------------------------------------------------------------------
All of the data generated in your IT infrastructure is seriously valuable.
Why? It contains a definitive record of application performance, security 
threats, fraudulent activity, and more. Splunk takes this data and makes 
sense of it. IT sense. And common sense.
http://p.sf.net/sfu/splunk-d2d-c2