Merge pull request #240 from BBMRI-ERIC/fix/resource_link

fix: unintentional modification of representative resources

src/main/java/eu/bbmri_eric/negotiator/database/model/Person.java

@@ -16,6 +16,7 @@
 import jakarta.persistence.SequenceGenerator;
 import jakarta.persistence.Table;
 import jakarta.validation.constraints.NotNull;
+import java.util.Collections;
 import java.util.HashSet;
 import java.util.Objects;
 import java.util.Set;
@@ -93,6 +94,13 @@ public void addResource(Resource resource) {
     resource.getRepresentatives().add(this);
   }
 
+  public Set<Resource> getResources() {
+    if (Objects.isNull(this.resources)) {
+      return Set.of();
+    }
+    return Collections.unmodifiableSet(this.resources);
+  }
+
   public void removeResource(Resource resource) {
     this.resources.remove(resource);
     resource.getRepresentatives().remove(this);

src/main/java/eu/bbmri_eric/negotiator/service/UserNotificationServiceImpl.java

@@ -38,7 +38,7 @@ public class UserNotificationServiceImpl implements UserNotificationService {
 
   private static Set<Resource> getResourcesInNegotiationRepresentedBy(
       Negotiation negotiation, Person representative) {
-    Set<Resource> overlappingResources = representative.getResources();
+    Set<Resource> overlappingResources = new HashSet<>(representative.getResources());
     overlappingResources.retainAll(negotiation.getResources());
     return overlappingResources;
   }