reference

Change-Id: Id9f64edd4e0f14502ba3b197ef5bcf95f88b3aba
Signed-off-by: Stephan Herrmann <stephan.herrmann@berlin.de>
Also-by: Vikas Chandra <Vikas.Chandra@in.ibm.com>
Reviewed-on: https://git.eclipse.org/r/c/jdt/eclipse.jdt.core/+/181631
Tested-by: JDT Bot <jdt-bot@eclipse.org>