public class XtextTaskCalculator implements IXtextBuilderParticipant {

	@Inject
	private XtextResourceFactory xtextResourceFactory;
	@Inject
	private ITaskElementChecker objElementChecker;

	@Override
	public void build(IBuildContext context, IProgressMonitor monitor) throws CoreException {
		for(IResourceDescription.Delta delta: context.getDeltas()) {
			URI uri = delta.getUri();
			IResource resource;
			if (uri.isPlatformResource()) {
				IPath path = new Path(uri.toPlatformString(true));
				resource = ResourcesPlugin.getWorkspace().getRoot().getFile(path);
			} else {
				// log warning "unexpected URI"
				continue;
			}

			if (resource.exists())
				resource.deleteMarkers(MarkerCreator.getMarkerType(), true, IResource.DEPTH_INFINITE);

			XtextResource xtextResource = (XtextResource) xtextResourceFactory.createResource(delta.getUri());
			try {
				xtextResource.load(null);
				new MarkerCreator(resource, objElementChecker, monitor).exec(xtextResource);
			} catch (IOException e) {
				// log error
			}
		}
	}
}