23. The medium of claim 17 further comprising executable code which when executed by a processor, causes the processor to perform steps further comprising: identifying an attribute test data as the negative test input data when the attribute test data complies negatively with an attribute constraint of a path predicate.
23. The medium of claim 17 further comprising executable code which when executed by a processor, causes the processor to perform steps further comprising: identifying an attribute test data as the negative test input data when the attribute test data complies negatively with an attribute constraint of a path predicate. 24. The medium of claim 23 , wherein the generation algorithm comprises a genetic algorithm when the attribute class is the string attribute class, a boundary value analysis and equivalence partitioning when the attribute class is the numeric attribute class with boundary constraint, and a genetic algorithm when the attribute class is the numeric attribute class with relational constraints.