Right now I have a really silly question but is not obvious to me how can I do the following thing in ST:
- let’s say I have an Object called ‘repository’ and this object has a get method repository.get( String resourceName). I cannot figure out how can I get access to this method in a ST?! (Jpublish will inject this object in the ST context before rendering a ST file)

I would like to write:
$repository.get( “path/to/a/resource”)$ or something a bit more complicated, where the resource is a variable: $repository.get ( page.getPath())$, where page is another object present in the ST context.

Can I even do all these? In Velocity (the default template language of JPublish) I can simply do this: $repository.get( $page.Path)

Thank you!
-florin

Questions like this are best asked on the stringtemplate mailing list over at http://www.stringtemplate.org/. Anyone using stringtemplate should subscribe to the mailinglist.

I’ll try to answer your question but if it isn’t sufficient you can move it to the list.

A very important feature of ST is that you can’t call arbitrary methods. repository.get(String path) is a method call. The reason is that methods can have side effects (properties can too but they usually don’t and shouldn’t). Calling a method can violate the push strategy - see section 7.1 in the “Enforcing Strict ModelView Separation in Template Engines” paper that says all data used by the template must be computed prior to invoking the template.

It looks like you are using the repository like a map. If the information in the repository is computed and available before the template is processed and getting a path has no side effects then you should be able to get at the data from the template. I can think of two ways to do this.

1) expose the structure of the repository as individual objects to ST so that you can access information as $repository.path.to.a.resource$. ST supports indirect property references but for one property at a time: $repository.(part1).(part2)$ will work but $repository.(path)$ will not. If it is common in your system to have paths that specify the property then option 1 may not be right for you.

2) treat the repository as a map. You will need to implement a map wrapper around your repository. The path then becomes a key into the map. $repository.(”path/to/a/resource”)$ would return the desired value. From ST point of view repository is a map and “path/to/a/resource” is a key. If your paths support complex expressions like XPath in XML then you need to think hard about model view separation and if you are breaking it.

A third less desirable option would be to modify ST so that it directly supported your path syntax.

There is also a simple web app demo using ST for web pages, demo that you can download from here: http://jpublish.googlecode.com/files/stdemo.war.zip, in case you’re interested. Any feedback will be highly appreciated.

Many thanks!
-florin