tm4j-users

RE: [TM4J-users] TM4Web/Velocity 0.2rc1 supports Hibernatebackends?

[Conal T. <Con...@vu...>]

Kal Ahmed wrote:

> I've checked in some changes for the TM4Web/Velocity package which
> provides a basic level of support for listing the topic maps in a
> database. You need a configuration like this:
>=20
> <provider name=3D"hibernate"=20
> factory=3D"org.tm4j.topicmap.hibernate.TopicMapProviderFactoryImpl">
>     <provider-properties>
>       <property name=3D"hibernate.connection.url"=20
> value=3D"jdbc:mysql://localhost/tm4mail"/>
>       <property name=3D"hibernate.connection.username" value=3D"***"/>
>       <property name=3D"hibernate.connection.password" value=3D"***"/>
>       <property name=3D"hibernate.dialect"=20
> value=3D"net.sf.hibernate.dialect.MySQLDialect"/>
>       <property name=3D"hibernate.connection.driver_class"=20
> value=3D"com.mysql.jdbc.Driver"/>
>     </provider-properties>  =20
>     <topicmaps template=3D"topicmap.vm"/>
>   </provider>
>=20
> Note the extra <topicmaps/> element that is required. The template
> attribute specifies the template to be used for the main=20
> topicmap page.
> With this update, you are forced to always use topic.vm to render
> topics, but I will work on adding support like you have in the normal
> <topicmap> element to specify the template(s) to use to render topics.

It's only vaguely related to Kal's post, but I thought I'd mention:

I haven't used the velocity templating engine, but I have used Cocoon to =
do templating. I've used Cocoon's JXTemplateGenerator, which is rather =
like XSLT with JXPath instead of XPath. JXPath gives you path-based =
access to Java object-graphs, e.g. x.getFoo().getBar() =3D> "x/foo/bar". =
So this is similar to Velocity, and similarly I have templates =
associated with various topic map objects.=20

I am keeping references to the individual JXTemplate files in the actual =
topic map, where they appear as occurrences of class topics. I had =
considered keeping a list of templates associated with different topics =
when I realised that this is what topic maps are for :-) I don't have a =
very sophisticated setup yet, but it does seem to me that referring to =
templates in the map itself is potentially a powerful technique. How =
does it work with the Velocity integration? Can you attach Velocity =
templates to particular classes of topics, for instance?

[TM4J-users] TM4Web Template Configuration WAS RE: TM4Web/Velocity 0.2rc1 supports Hibernatebackends?

[Kal A. <ka...@te...>]

On Tue, 2004-09-28 at 05:47, Conal Tuohy wrote:

> It's only vaguely related to Kal's post, but I thought I'd mention:
> 
> I haven't used the velocity templating engine, but I have used Cocoon to do templating. I've used Cocoon's JXTemplateGenerator, which is rather like XSLT with JXPath instead of XPath. JXPath gives you path-based access to Java object-graphs, e.g. x.getFoo().getBar() => "x/foo/bar". So this is similar to Velocity, and similarly I have templates associated with various topic map objects. 
> 
> I am keeping references to the individual JXTemplate files in the actual topic map, where they appear as occurrences of class topics. I had considered keeping a list of templates associated with different topics when I realised that this is what topic maps are for :-) I don't have a very sophisticated setup yet, but it does seem to me that referring to templates in the map itself is potentially a powerful technique. How does it work with the Velocity integration? Can you attach Velocity templates to particular classes of topics, for instance?
> 
> 

That sounds interesting - I haven't got really deeply into Cocoon so
JXPath just completely passed me by :)

In terms of associating templates with classes of topics for the
Velocity integration, currently that is done by an external (XML)
configuration file. The format allows you to specify a topic by its
subject indicator and then specify a template. You can scope the
application of the template to apply to:
  1) Just the specified topic
  2) Any instance of the topic
  3) Any subclass of the topic
(2) respects the subclass-superclass hierarchy, and the code attempts to
locate the closest class in the hierarchy. So if you have a template
person.vm scoped for instances of a topic 'Person' and then have 'Man'
and 'Woman' as subclasses, person.vm would be used to render instances
of 'Person', 'Man' and 'Woman'.

One thing that I have found really useful in the Velocity framework is
the concept of the toolbox that contains utility classes that are
initialised either per-app, per-session or per-request. It makes it
quite easy to integrate helpers like the TologTool. Also I find it
useful to have a simple Factory helper (because there doesn't seem to be
a way to initialise new objects in Velocity's templating language) -
when you combine this with Mango's functional classes you can make lots
of reusable helper objects that make writing the templates quite easy.
Does the Cocoon framework have similar helpers ?

Cheers,

Kal
-- 
Kal Ahmed <ka...@te...>
techquila