在应用程序的开发过程中合理使用设计模式，不仅能够解决实际问题，提高开发效率，而且还能够让程序结构更为清晰合理，对达到“低耦合、高内聚”的设计目的有着很大的帮助。目前网上有很多介绍设计模式的文章，有的也自成体系，基本涵盖了GoF的所有模式(Rational use of design patterns in the development process of the application, not only can solve practical problems, improve development efficiency, but also can make the program structure more clear and reasonable, has a great help to achieve the design purpose of low coupling and high cohesion ". At present, there are many design patterns introduced articles online, some are self-contained, covering all modes of GoF, but most articles are similar to some simple type design as an example (such as Animal, Cat, Dog, Fruit, Apple, Banana etc.), although easy to understand, but after reading, found from the actual there is still a certain distance application. In view of this situation)