An Extensible Contract Verifier for AspectJContract Verifier • August 19th, 2006
Weaving in AspectJ does not always modify the behavior of a program according to the intention of a programmer. To verify whether a behavior change during weaving satis- fies this intention, we have proposed COW. It is a language for describing constraints on weaving in terms of a con- tract for executing weaving correctly. A contract consists of pre-conditions, post-conditions, and invariants of weaving. By using these conditions, a programmer can specify how a program should behave before and after weaving. The con- ditions are described in predicate logic that represents the behavior of a program. COW provides the primitive pred- icates for describing the program behavior. However, it is not necessarily true that such behavior verification is al- ways effective in determining whether weaving is executed according to the intention of a programmer. For instance, the behavior verification COW provides is not effective in determining whether the structure of a program is correctly chang
