Using Annotations to Identify primary for a secondary object if no owner reference can be added (#1197)

Author: csviri

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/dependent/kubernetes/KubernetesDependentResource.java

@@ -91,6 +91,20 @@ private SecondaryToPrimaryMapper<R> getSecondaryToPrimaryMapper() {
     }
   }
 
+  @SuppressWarnings("unchecked")
+  private SecondaryToPrimaryMapper<R> getSecondaryToPrimaryMapper() {
+    if (this instanceof SecondaryToPrimaryMapper) {
+      return (SecondaryToPrimaryMapper<R>) this;
+    } else if (garbageCollected) {
+      return Mappers.fromOwnerReference();
+    } else if (useDefaultAnnotationsToIdentifyPrimary()) {
+      return Mappers.fromDefaultAnnotations();
+    } else {
+      throw new OperatorException("Provide a SecondaryToPrimaryMapper to associate " +
+          "this resource with the primary resource. DependentResource: " + getClass().getName());
+    }
+  }
+
   /**
    * Use to share informers between event more resources.
    *