Merge branch 'refs/heads/develop' into 117-duplicate-userrefid-causing-lockup-on-a-parallel-upload

# Conflicts:
#	VERSION.txt

VERSION.txt

-2.2.9 Fix user ref creation failing on parallel requests.
+2.2.10 Fix user ref creation failing on parallel requests.
+2.2.9 Add check to prevent reviving an expired training instance.
 2.2.8 Add check for training definition being in use when trying to add, remove and update tasks.
 2.2.7 Add more descriptive message when training phase contains no tasks. Add answer required field to Adaptive Question.
 2.2.6 Implement the ANSWER tag replacing in task solution.

src/main/java/cz/muni/ics/kypo/training/adaptive/service/training/TrainingInstanceService.java

@@ -135,6 +135,7 @@ public class TrainingInstanceService {
     public String update(TrainingInstance trainingInstanceToUpdate) {
         validateStartAndEndTime(trainingInstanceToUpdate);
         TrainingInstance trainingInstance = findById(trainingInstanceToUpdate.getId());
+        checkNotRevivingAnExpiredInstance(trainingInstanceToUpdate, trainingInstance);
         //add original organizers to update
         trainingInstanceToUpdate.setOrganizers(new HashSet<>(trainingInstance.getOrganizers()));
         addLoggedInUserAsOrganizerToTrainingInstance(trainingInstanceToUpdate);
@@ -176,6 +177,14 @@ public class TrainingInstanceService {
         }
     }
 
+    private void checkNotRevivingAnExpiredInstance(TrainingInstance trainingInstanceToUpdate, TrainingInstance currentTrainingInstance) {
+        if (currentTrainingInstance.finished() && !trainingInstanceToUpdate.finished()) {
+            throw new EntityConflictException(new EntityErrorDetail(TrainingInstance.class, "id",
+                    trainingInstanceToUpdate.getId().getClass(), trainingInstanceToUpdate.getId(),
+                    "End time of an expired instance cannot be set to the future."));
+        }
+    }
+
     private void checkChangedFieldsOfTrainingInstance(TrainingInstance trainingInstanceToUpdate, TrainingInstance currentTrainingInstance) {
         if (!currentTrainingInstance.getStartTime().equals(trainingInstanceToUpdate.getStartTime())) {
             throw new EntityConflictException(new EntityErrorDetail(TrainingInstance.class, "id", Long.class, trainingInstanceToUpdate.getId(),