How to add property tag inside target tag in build.xml in ant

Question

i have the same source code for 5 projects and i want to build each project with the same build file in ANT. i want to build the code using the name of each project.

Answer 1

I suggest that you define targets in your build.xml file called "DEV" and "PROD" and then invoke Ant as:

ant DEV or

ant PROD If you want to stick with your current approach of using a system property to select the target, then @krock's answer seems to be the way to go. (But I don't see any advantage in that approach though.)

Answer 2

Define a userproperty with your projectname like that :

ant -f build.xml -Dprojectname=foobar

and use it in your buildfile :

<project>

<echo>$${projectname} => ${projectname}</echo> 

<!-- the real work ... -->

</project>

output :

[echo] ${projectname} => foobar

-- EDIT --

You may use some kind of loop, f.e. :

ant -f build.xml -Dprojectnames=project1,project2,project3

wrap your steps (checkout, compile ...) in a macrodef and call it for every project :

<project>

 <macrodef name="foobar">
  <attribute name="projectname"/>
   <sequential>
    <echo>Projectname : @{projectname}</echo>

    <!-- the real work -->

   </sequential>
 </macrodef>

 <script language="javascript">
 <![CDATA[
   var projects = project.getProperty('projectnames').split(',');
   for (i=0; i < projects.length; i++) {
    macro = project.createTask('foobar');
    macro.setDynamicAttribute('projectname', projects[i]);
    macro.perform();
   }
  ]]>
  </script>

</project>

output :

[echo] Projectname : project1
[echo] Projectname : project2
[echo] Projectname : project3

You may also create ant targets instead of macrodef.
Javascript engine is contained in Java >= 1.6.0_06, so no extra libraries needed.
Also there are more sophisticated approaches, f.e. using a xmlproperty file holding your projectnames combined with xmltask (= xmldriven build) which provides some looping mechanism via xpath expressions.
It depends upon the complexity of your buildscript.