extending velocity

[Karthik Guru]

What are the typical extension points provided by velocity? I mean something like the way struts allows us to plug in our request processor etc.
What are the reasons someone might want to extend velocity..again some practical examles would help. Say am using velocity with struts / Spring, i guess that would mean that someone has already extended velocity for me so that it can be easier to make it work with struts/spring. But are there likely to be situations when i would have to extend velocity further?

[Alexandru Popescu]

I am not quite sure what these extensions would be. I have for example an automatic context build, but this is very specific to my scenarios.

./pope

[Rob Harrop]

Karthik,

There are a few ways to extend Velocity and the template processing pipeline.

You can hook into template processing using event handlers.

Velocity works against the Context interface so you can implement your own Context if you want. This is quite useful for building an adaptor to some other model data source.

You an encapsulate simple template fragments into Velocity macros and you can use your own tools to provide additional utilities.

If you find that macros and tools don't do what you want, then you can hook in custom directives using the user directive approach.

Rob

[Karthik Guru]

thanks rob for a detailed explanation. I shall probably try out a couple of things that you have suggested