随着软件开发规模的扩大，传统的面向过程的软件开发方法给软件的复用、调试、维护带来了很大的困难。为了解决满足软件开发的需求，人们提出了面向对象程序设计（Object Oriented Programming，OOP）的思想。如今面向对象的思想已经深入人心，已经应用到程序设计和软件开发、数据库系统、人工智能等很多领域-With the expansion of software development, the traditional process-oriented approach to software development, software reuse, debugging and maintenance has led to great difficulties. In order to solve to meet the needs of software development, have been proposed object-oriented programming (Object Oriented Programming, OOP) ideas. Today, object-oriented thinking has gained recognition, has been applied to programming and software development, database systems, artificial intelligence, and many other fields