Using a different version of Ant

The Eclipse platform provides Ant 1.5.2 as a plug-in library. When running an Ant buildfile in the Workbench, version 1.5.2 is used by default. It is possible to use different versions, although they are not supported. There are at least two ways of using a different version of Ant:

Changing the Ant classpath:
When Ant runs a buildfile, it looks for the necessary classes on the Ant classpath. The Ant classpath consists of the plug-ins contributing new tasks, types or libraries, plus the classpath defined in the external tools preferences. To access the preferences, click Window > Preferences > Ant > Runtime. The two JARs related to Ant 1.5.2 are ant.jar and optional.jar. Remove these JARs and add the ones from the desired Ant version.

Note that explicitly adding the Xerces JARs to the runtime Ant classpath is no longer required and will cause problems. The Xerces classes are loaded from the org.apache.xerces plug-in provided with Eclipse. For most Ant distributions, the Xerces JARs cannot even be in the same physical location as the ant.jar and optional.jar. This results from the Ant JARs containing manifest files which contain classpath entries pointing to the Xerces JARs.

After you change the Ant classpath, all future Ant builds will use the updated version instead of the default. To restore the Ant classpath to its original state, Restore Defaults button on the properties page.

Using Ant as an external tool:
When changing the Ant classpath is not an option, or if you just want to test a newer version or beta version of Ant, using it as an external tool can be a better solution. Usually when it is running in the Workbench, the Ant script itself is considered to be a external tool, but this is not the only way. To install a binary distribution of Ant as an external tool (Note: These steps are for Windows, but similar methods can be used for other operating systems):
  1. Download and install the binary version of Ant from http://ant.apache.org .
  2. Click Run > External Tools > External Tools....
  3. Click Program
  4. Click New.
  5. Enter a name for your external tool (for example, External Ant).
  6. For the Location field, click Browse File System.
  7. Find and select a file called ant.bat (it should be in the bin folder of your Ant installation).
  8. In the Arguments field enter the arguments for your script that would normally enter for running the script outside of the Workbench.
  9. In the Working Directory field enter the directory of your buildfile.
  10. Click Run to execute the buildfile.

When you run Ant as an external tool, none of the tasks or types contributed by Eclipse will work. Also, the Ant classpath preference has no effect in the script execution.

Related concepts
Ant Support
External tools

Related tasks
Running Ant buildfiles
Running external tools
Modifying the Ant classpath
Adding new Ant tasks and types

 
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