code: @SuppressWarnings("unchecked")
    public boolean contains(Marker container, Marker test) {
      for (FieldPartitioner field : Accessor.getDefault().getFieldPartitioners(strategy)) {
        Object containerValue = container.valueFor(field);
        if (containerValue != null) {
          Object testValue = test.valueFor(field);
          if (testValue == null || field.compare(containerValue, testValue) != 0) {
            return false;
          }
        }
        /*
         * Rather than returning true if containerValue is null, this treats
         * null as a wildcard. Everything matches null, so all non-null fields
         * will be checked.
         */
      }
      return true;
    }
docs: Returns true if {@code container} contains {@code test}, false otherwise.
  
  Fields for which {@code set} has no value
  ({@link Marker#valueFor(FieldPartitioner)} returns
  null) are treated as wildcards and always match.
  
  All fields in the {@link PartitionStrategy} are compared.
  
  @param container a {@code Marker} that defines a set of partitions
  @param test a {@code Marker} that may be a subset of {@code container}
  @return
  {@code true} if the partitions in {@code test} are a subset of
  {@code container}, {@code false} otherwise