Both the abstractions and their implementations should be extensible by subclassing. In this case, the Bridge pattern lets you combine the different abstractions and implementations and extend them independently.

• 类的抽象以及它的实现都应该可以通过生成子类的方法加以扩充。这是Bridge模式使你可以对不同的抽象接口和实现部分进行组合,并分别对它们进行扩充。