RE: [Springframework-developer] sanbox spring cleaning

[Mark P. <Mar...@Co...>]

Hi,

I put the selector in there for when we have container-like JMS support. 
There are also some docs in the sandbox if you want to read more about it.

Basically it allows you to apply JMS-selector SQL to any Java object. 
These can be normal pojo's or the jms message content itself.  To use the
library you plug in a 'value-adapter' to the parser so that it can
evaluate the sql string against your object of choice.  These can be
POJOs, or a MapMessage or whatever.

The 'mdb' configuation file can specify this string so that an incoming
message/object is directed to a particular processing chain if the
selector matched.  I've found this to be a very effective means to
organize processing of message in complex JMS apps.  There are frequently
so many different actions you want to on different message types that are
delivered on the same destination but there are typically just 1 or 2
destinations.  You therefore need some logic to branch off the single
callback onMessage(message m) to handle each request.  The JMS properties
section can be used for this purpose but it is more of a subscription
filtering technique and often people start putting every property of the
object inside the property section just to get this functionality.  I feel
the selector addresses this issue nicely.

There is a recent project from jakarta commons that offers similar
functionality but it is based on XPath instead of sql.

http://jakarta.apache.org/commons/jxpath/

Interested to hear your opinions...


-Mark


> +1 for removing it if noone objects
>
>
> -----Original Message-----
> From: spr...@li...
> [mailto:spr...@li...]On Behalf Of
> Keith Donald
> Sent: Tuesday, October 12, 2004 5:49 PM
> To: spr...@li...
> Subject: [Springframework-developer] sanbox spring cleaning
>
>
>
> I've been doing some spring cleaning in the sandbox: what are the
> org.springframework.selector package and related subpackages?  Is anyone
> using this?  Do we intend do move this forward in any way?  I know that
> it's been there for at least several months - April or so I believe.
>
>
>
> If it's not being used and there are no objections, can we remove it?
> Thanks, Keith
>
>