The approach of this paper proposes a new concept of test which represents a way to compare the behaviors of methods in sub-classes and their original versions in the super-classes for an object oriented specification. The test process gives the conditions where the comparison can induce a similar behavior. The result of this test constitutes a solid basis to reuse the inherited specifications in the sub-classes for testing the conformity of overriding methods. The main objective of the proposed work is to find the relationship between the test model of an overriding method and its overridden method using the constraint propagation. Our approach shows that the conformity testing in sub-classes is based on the similarity testing between overriding and overridden methods. The implementation of this approach is based on a random generation of test data and analysis by formal proof.