Ant var and property scope

Question

I have a main build script that calls various targets. One of these targets needs to store a value and another target needs to display it. Obviously this is not working so I think it may be related to scope. I've tried var, property, and declaring the property outside of target1. Since var seems to be mutable, it looks like I need to use it instead, but each time my output is empty.

Main script

<antcall target="target1"/>
<antcall target="display"/>

In target1:

<var name="myVar" value="${anotherVar}"/>

In display:

<echo>${myVar}</echo>

Answer 1

antcall will start the ant target in a new project and will not affect the main project in any way. Try runtarget from antcontrib to run the targets in the same project.

Answer 2

You can call multiple targets with one antcall element. These targets will then share a single project instance including the properties defined. To do this specify the targets as nested elements like this:

<antcall>
  <target name="target1"/>
  <target name="display"/>
</antcall>

Answer 3

Another option I found was the antcallback, and it appears to work. This limits what is returned to just a particular list of values, which seems inherently safer than opening up the scope of the whole target (as it sets, creates, modifies many var and properties).

<antcallback target="target1" return="myVar"/>
<antcall target="display"/>

I think all of these are valid solutions, it just depends on what level you want to change the variable scope at.

Answer 4

Do you really need to use <antcall>? Can you use target dependencies instead?

As you suspect, using <antcall> essentially creates a new scope.

Answer 5

Using antcallback within the groovy task won't work as they have used a java reserved word (return) as the name of one of the attributes!