定义component,在我们的例子中是超类drink,注意它是一个抽象类
*----------------------------------------------------------------------*
* INCLUDE ZBOBO_DP_003_IF_CL *
*----------------------------------------------------------------------*
*For the Decorator pattern, normally using an abstract super class
*And the Decorator class inherite from the super class also as an
* abstract class
*Super abstract class with drink
class drink definition abstract.
public section.
data: desc type string.
methods:
* Get the drink's description
getdesc returning value(de) type string,
* Because the cost must be calculate from every concrete material
* It should be an abstract method
cost abstract returning value(co) type f.
endclass.
*Implement the drink class
class drink implementation.
method getdesc.
* Return the description
de = desc.
endmethod.
endclass.
* INCLUDE ZBOBO_DP_003_IF_CL *
*----------------------------------------------------------------------*
*For the Decorator pattern, normally using an abstract super class
*And the Decorator class inherite from the super class also as an
* abstract class
*Super abstract class with drink
class drink definition abstract.
public section.
data: desc type string.
methods:
* Get the drink's description
getdesc returning value(de) type string,
* Because the cost must be calculate from every concrete material
* It should be an abstract method
cost abstract returning value(co) type f.
endclass.
*Implement the drink class
class drink implementation.
method getdesc.
* Return the description
de = desc.
endmethod.
endclass.
定义concrete component，在我们的例子中，它是饮料类的一个子类darkroast
*An concrete class for drink, as one need to be decorated
class darkroast definition inheriting from drink.
public section.
methods:
* initialization
constructor,
* The subclass should implement abstract method from super
cost redefinition.
endclass.
*Implement darkroast
class darkroast implementation.
method constructor.
call method super->constructor.
* Give a new description
desc = 'Darkroast'.
endmethod.
method cost.
* Get the raw material cost
co = '1.99'.
endmethod.
endclass.
class darkroast definition inheriting from drink.
public section.
methods:
* initialization
constructor,
* The subclass should implement abstract method from super
cost redefinition.
endclass.
*Implement darkroast
class darkroast implementation.
method constructor.
call method super->constructor.
* Give a new description
desc = 'Darkroast'.
endmethod.
method cost.
* Get the raw material cost
co = '1.99'.
endmethod.
endclass.
