Head First Design Patterns 阅读笔记之八: the Template Method Pattern

这一模式的正式定义为：

The Template Method Pattern defines the skeleton of an algorithm in a method, deferring some steps to subclasses. Template Method lets subclasses redefine certain steps of an algorithm without changing the algorithm’s structure.

可以看出这一模式主要是关于为算法创建模板的，那什么是模板呢？书中是这么说的

A template is a method that defines an algorithm as a set of steps，and one or more of these steps is defined to be abstract and implemented by subclass。

这样就确保了算法的结构不会改变，子类会提供算法的部分实现。