NPE fixed in BatchRESTService

src/main/java/org/genesys2/server/service/impl/BatchRESTServiceImpl.java

@@ -597,7 +597,7 @@ public class BatchRESTServiceImpl implements BatchRESTService {
 		UpdateTargets targets = new UpdateTargets();
 		targets.addKwsItem(TermConstants.PASSPORT_DATA);
 		savedData.stream().map(a -> a.getDoi()).filter(doi -> doi != null).forEach(doi -> targets.addDoisItem(doi));
-		if (targets.getDois().size() > 0) {
+		if (targets.getDois() != null && targets.getDois().size() > 0) {
 			try {
 				LOG.debug("Updating GLIS for {} accessions with DOIs", targets.getDois().size());
 				List<UpdatedTarget> glisResponse = glisGenesysApi.registerGenesysAsTarget(targets);