In Ant, how can I dynamically build a property that references a property file?

Question

I am using Input tasks to collect specific property values and I want to concatenate those into one property value that references my properties file.

I can generate

Answer 1

Additional example using the Props antlib.
Needs Ant >= 1.8.0 (works fine with latest Ant version 1.9.4) and Props antlib binaries.

The current build.xml in official Props antlib GIT Repository (or here) doesn't work out of the box :

BUILD FAILED
Target "compile" does not exist in the project "props".

Get the sources of props antlib and unpack in filesystem.
Get the sources of antlibs-common and unpack contents to ../ant-antlibs-props-master/common
Run ant antlib for building the jar :

[jar] Building jar: c:\area51\ant-antlibs-props-master\build\lib\ant-props-1.0Alpha.jar

Otherwise get the binaries from MVNRepository or here

The examples in ../antunit are quite helpful. For nested properties look in nested-test.xml
Put the ant-props.jar on ant classpath.

output :

Buildfile: c:\area51\ant\tryme.xml
    [input] Enter Location:
west
    [input] Enter Sandbox:
1
     [echo] TaPwxOsa

BUILD SUCCESSFUL
Total time: 4 seconds