设计模式--结构模式--装饰模式--Java
decoratorintentAttachadditional responsibilities to an object dynamically. Decorators provide aflexible alternative to subclassing for extending functionality为一个类动态地增加一些功能，比通过继承更灵活umlparticipantsComponentdefinesthe interface for objects that can have responsibilities added to them dynamically.为其定义功能接口ConcreteComponentdefines an object to which additional responsibilities can be attached功能具体实现Decoratormaintainsa reference to a Component object and defines an interface that conforms toComponent's interface持有component引用，并定义功能接口ConcreteDecoratoradd sresponsibilities to the component.为component添加实现功能Consequence效果More flexibility than static inheritance.比静态继承更灵活Lots of little objects. A design that uses Decorator often results in systems composed of lots of little objects that all look alike.需要较少的对象。会导致有大量较小的对象。相关模式•Ad a p t e r模式：D e c o r a t o r模式不同于A d a p t e r模式，因为装饰仅改变对象的职责而不改变它的接口；而适配器将给对象一个全新的接口。•Co m p o s i t e模式：可以将装饰视为一个退化的、仅有一个组件的组合。然而，装饰仅给对象添加一些额外的职责—它的目的不在于对象聚集。•St r a t e g y模式：用一个装饰你可以改变对象的外表；而S t r a t e g y模式使得你可以改变对象的内核。这是改变对象的两种途径。JDK-InputStream 分析通过观察FileInputStream构造函数，其不属于decorator。JDK-Reader 分析
补充：软件开发 , Java ,
