Replace Type Code with Subclasses的主要作用是搭建一个舞台,让Replace Conditional with Polymorphism得以一展身手。如果宿主类没有出现条件表达式,那么Replace Type Code with Class更合适,并且风险也更低。 使用Replace Type Code with Subclasses的另一个原因就是,宿主类中出
这样以后想要增加一种方法就只要创建一个子类,然后修改一下父类的工厂函数就可以了,这种用于Replace Conditional with Polymorphism(用多态代替条件语句)或者用Replace Type Code with State/Strategy(用State/Strategy代替类型码)就方便了
Problem: You have a coded type that directly affects program behavior (values of this field trigger various code in conditionals). Solution: Create subclasses for each value of the coded type. Then extract the relevant behaviors from the original class t
Problem: You have a coded type that affects behavior but you cannot use subclasses to get rid of it. Solution: Replace type code with a state object. If it is necessary to replace a field value with type code, another state object is “plugged in”.
Replace Type Code With Subclasses(以子类取代型别码)将不需要改变的type code用子类来代替,这样子每添加一个型别码的同时,我们只需要新增一个子类,然后再switch语句中加一句构造就好了。剩下的,有关于新添加型别的特性和功能可以独立到新的subclass中,不需要修改什么。
Replace Type Code with State/Strategy(以state/strategy取代型别码)和Replace Type Code With Subclasses(以子类取代型别码)十分的类似,都是通过多态的方式,将type code绑定到固定的子类上面,其中不同的是,Replace Type Code With Subclasses(以子类取代型别码)绑定的是对象的子类,可以增添某种type特有的特性。而Re...
@danvk, you should be able to use flow type syntax withReact.Componentsubclasses now. If that is posing any issues for you, please reopen this. Thanks for the report! samwgoldmanclosed this ascompletedJun 24, 2015 Member samwgoldmancommentedJul 21, 2015 ...
source_location, msg), code=code, prefix=False) 146 146 147 147 def _prepare_to_generate_rule(self): 148 148 """Should be overridden. """ 149 - self.error_exit('_prepare_to_generate_rule should be overridden in subclasses') 149 + self.fatal('_prepare_to_generate_rule should ...
/** Replaces constructor call with standard non optimized invocation code. Up to subclasses to override this behaviour */ protected void replaceConCallInCon(ConByConDetail cd)throws CannotCompileException, NotFoundException { String replaced = conByConInfoFromWeakReference("info", cd.callerInfoField) ...
“chemical libraries” are then screened in one or more assays, as described herein, to identify those library members (particular chemical species or subclasses) that display a desired characteristic activity. The compounds thus identified can serve as conventional “lead compounds” or can themselves...