设计模式（Design Pattern）描述了软件开发过程中若干重复出现的问题的解决方案，这些方案不是由过程、算法等底层程序构造实体实现，而是由软件系统中类与类之间或不同类的对象之间的共生关系组成。 -Design patterns (Design Pattern) describes the solution to the problem of software development process is repeated, these programs are not by the process and algorithms underlying program structure entities, but by class and class software systems, or between objects of different classesthe symbiotic relationship between the composition.