Developing Ant tasks and types within Eclipse

Ant tasks and types must be loaded by an Ant classloader instead of a plug-in classloader. This can cause problems when developing and testing new tasks and types to be run in the same VM as Eclipse. To avoid these issues, it is necessary to store the tasks and types in a location that is not visible to any plug-in classloader.

The following guidelines should be followed when developing and debugging new tasks and types to be run within the same VM as Eclipse.

• Contributed Ant tasks or types should be defined in their own source folder within a plug-in (i.e. separate from the source folders containing regular plug-in classes)
• Each source folder containing the Ant tasks and types should have its own output location that does not overlap with the output location of the regular plug-in classes.
• When testing/debugging the new Ant tasks or types using PDE Launch, additional configuration is required:
  • the project contributing the Ant tasks or types must be configured to exclude the output folders containing the Ant tasks and types. Use the Properties dialog for the project to correctly configure the Plug-in Development > Runtime Classpath by removing the Ant output directories from the plug-ins classpath.
  • The JAR file containing the Ant tasks and types and specified in the org.eclipse.ant.core.extraClasspathEntries extension, must be built manually, or using an external tool builder.

The org.eclipse.ant.core plugin can be used as an example of how to set up a plugin that contributes tasks within Eclipse. For development and testing of this plugin within Eclipse, an external tool builder explictly generates the tasks JAR when triggered on specific resource changes.

Also see Contributing tasks and types.