【java设计模式】【结构模式Structural Pattern】装饰模式Decorator Pattern

 1 public class Client {
 2     public static void main(String[] args) {
 3         Component component=new ConcreteComponent();
 4         component=new ConcreteDecoratorA(component);
 5         component=new ConcreteDecoratorB(component);
 6         component.doSth();
 7     }
 8 }
 9 interface Component{
10     void doSth();
11 }
12 class ConcreteComponent implements Component{
13     @Override
14     public void doSth() {
15         System.out.println("This is ConcreteComponent.doSth()");
16     }
17 }
18 abstract class Decorator implements Component{}
19 class ConcreteDecoratorA extends Decorator{
20     private Component component;
21     public ConcreteDecoratorA(Component component){
22         this.component=component;
23     }
24     @Override
25     public void doSth() {
26         concreteDecoratorA_method();
27         component.doSth();        
28     }
29     public void concreteDecoratorA_method(){
30         System.out.println("This is ConcreteDecoratorA.concreteDecoratorA_method()");
31     }
32 }
33 class ConcreteDecoratorB extends Decorator{
34     private Component component;
35     public ConcreteDecoratorB(Component component){
36         this.component=component;
37     }
38     @Override
39     public void doSth() {        
40         concreteDecoratorB_method();
41         component.doSth();
42     }
43     public void concreteDecoratorB_method(){
44         System.out.println("This is ConcreteDecoratorB.concreteDecoratorB_method()");
45     }
46 }