The Research On Integrity And Consistency Of Class Structure Based On XML

Object-oriented method is a new program design method. Program is designed through object, inherit, encapsulation, message, etc. is the basic thinking of object-oriented method, object-oriented method includes analysis, design and program. The task of object-oriented analysis is build a class structure through analyzing problem domain. Logic class structure is highly important to object-oriented design.Class is the basic element of class structure . It is research that class should hold four basic feature: integrality and sufficiency, primitiveness, high cohesion, low coupling in this paper. Then quantitative indicators are given to measure class, they are weighted methods for per class, depth of the inheritance tree, number of children, method inheritance factor, attribute inheritance factor, coupling factor and polymorphism factor. Use above seven method can know the degree of complex and other character of each class.There are four kind of relation between class. They are generic-special relation, comprehensive-partitive relation, static relation, dynamic relation. It is emphasis on contravariance rule, covariance rule and closed-behavior rule that generic-special relation must abide in this paper. These rule may ensure consistency on behavior and state between subclass and superclass, so user can use the generic-special relation' s benefit in security. Refer to reference integrity of relation database module (not allow using metadata that not exist) , given concept to reference integrity of class structure. The concept is that if a class structure is reference integrity then the graph must be connective.At last, proposes to describe class structure use XML, and complete analysis and design of class structure verify tool.