[DS-2976] Ensure all database entities have a protected constructor

dspace-api/src/main/java/org/dspace/eperson/EPerson.java

@@ -84,7 +84,14 @@ public class EPerson extends DSpaceObject implements DSpaceObjectLegacySupport
     @Transient
     protected transient EPersonService ePersonService;
 
-    protected EPerson() {
+    /**
+     * Protected constructor, create object using:
+     * {@link org.dspace.eperson.service.EPersonService#create(Context)}
+     *
+     */
+    protected EPerson()
+    {
+
     }
 
     @Override