> From: Sam Ruby/Raleigh/IBM [mailto:[EMAIL PROTECTED]
>
> Jose Alberto Fernandez wrote:
> >
> > BTW, can someone tell me how to do introspection
> > on a piece of BSF script? I would like to find
> > out what functions are defined on a script.
> > And its parameter type information.
>
> Not possible. To BSF, it is simply a string. In fact, many scripting
> languages don't even have the concept of staticly defined functions or
> parameter type information.
>
But in BSF there is a call(...) API to call a function defined in a script.
So it seems that there should be a way to identify the functions that are
there.
What I would like to be able to do is the following:
1) Being able to define a task as a script:
<scriptdef name="mytask" language="javascript" >
function setArg1(...){...}
function setArg2(...){...}
function createArg3(){...}
function init(){...}
function execute(){...}
</scriptdef>
2) Such task will do as Nico suggested, define the task using
a predefined java class that will know how to find and execute the script.
This is the part I have a little fuzzy, where to store the script
associated with the task, since in the current ANT the task table only
stores
instances of classes. I need to store actual script instances.
3) Use the task as any normal task:
<target .... >
<mytask arg1="a" arg2="b" >
<arg3 ... />
</mytask>
</target>
4) And of course, being able to define such task in the proposed tasklib.xml
model that we have been talking for 2.0.
In other words, a user should see no difference between Java based tasks and
script based tasks from the point of view of usability. I should be able to
define
something using scripts in a tasklib, and then in the future reimplement it
in
Java without a need to change the build.xml file.
The best would be to be able to say:
<taskdef name="mytask" ....>
<script ....>
</script>
</taskdef>
But given that taskdef is core and script is optional, I do not know how we
could
settle this, unless we modify <taskdef> to provide a more open architecture.
For example, do not assume tasks are only classes, but use a factory pattern
to access them.
<taskdef name="copy" >
<factory classname="org.apache.ant.DefaultTaskFactory">
org.apache.ant.taskdefs.Copy
</factory>
</taskdef>
The above would be equivalent for the current shorthand definition:
<taskdef name="copy" classname="org.apache.ant.taskdefs.Copy" />
But with this syntax the proposed script could be defined as:
<taskdef name="mytask" >
<factory classname="org.apache.ant.taskdefs.optional.ScriptFactory">
function setArg1(...){...}
function setArg2(...){...}
function createArg3(){...}
function init(){...}
function execute(){...}
</factory>
</taskdef>
Which means that it is upto the Factory to interpret the String as
appropriate.
Does this makes sense?
Jose Alberto
