Java设计模式之抽象工厂模式
ABSTRACT FACTORY?（Object Creational）?
Purpose?
Provide an interface that delegates creation calls to one or?
more concrete classes in order to deliver specific objects.?
Use When?
n The creation of objects should be independent of the system?
utilizing them.?
1 Systems should be capable of using multiple families of objects.?
2 Families of objects must be used together.?
3 Libraries must be published without exposing implementation?
details.?
4 Concrete classes should be decoupled from clients.?
Example?
Email editors will allow for editing in multiple formats including?
plain text, rich text, and HTML. Depending on the format being?
used, different objects will need to be created. If the message?
is plain text then there could be a body object that represented?
just plain text and an attachment object that simply encrypted?
the attachment into Base64. If the message is HTML then the?
body object would represent HTML encoded text and the?
attachment object would allow for inline representation and a?
standard attachment. By utilizing an abstract factory for creation?
we can then ensure that the appropriate object sets are created?
based upon the style of email that is being sent.?
new?ConcreteFactory();??
