code: private static List<Class> checkMergePolicy(SplitBrainMergeTypeProvider mergeTypeProvider, Object mergePolicyInstance) {
          if (mergePolicyInstance instanceof SplitBrainMergePolicy) {
              return checkSplitBrainMergePolicy(mergeTypeProvider, (SplitBrainMergePolicy) mergePolicyInstance);
          }
          return null;
      }
docs: Checks if a {@link SplitBrainMergeTypeProvider} provides all required types of a given merge policy instance.
  
  @param mergeTypeProvider   the {@link SplitBrainMergeTypeProvider} to retrieve the provided merge types
  @param mergePolicyInstance the merge policy instance
  @return a list of the required merge types if the merge policy is a {@link SplitBrainMergePolicy}, {@code null} otherwise