public CriteriaModel criteria() {
    CriteriaModel model = criteriaModel;
    if (model == null) {
      model = new CriteriaModel(this);
      criteriaModel = model;
    }

    return model;
  }
Expose criteria metadata like list of matchers for current attribute.
value-processor/src/org/immutables/value/processor/meta/ValueAttribute.java