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

 public class Client {
     public static void main(String[] args) {
         Component component=new ConcreteComponent();
         component=new ConcreteDecoratorA(component);
         component=new ConcreteDecoratorB(component);
         component.doSth();
     }
 }
 interface Component{
     void doSth();
 }
 class ConcreteComponent implements Component{
     @Override
     public void doSth() {
         System.out.println("This is ConcreteComponent.doSth()");
     }
 }
 abstract class Decorator implements Component{}
 class ConcreteDecoratorA extends Decorator{
     private Component component;
     public ConcreteDecoratorA(Component component){
         this.component=component;
     }
     @Override
     public void doSth() {
         concreteDecoratorA_method();
         component.doSth();
     }
     public void concreteDecoratorA_method(){
         System.out.println("This is ConcreteDecoratorA.concreteDecoratorA_method()");
     }
 }
 class ConcreteDecoratorB extends Decorator{
     private Component component;
     public ConcreteDecoratorB(Component component){
         this.component=component;
     }
     @Override
     public void doSth() {
         concreteDecoratorB_method();
         component.doSth();
     }
     public void concreteDecoratorB_method(){
         System.out.println("This is ConcreteDecoratorB.concreteDecoratorB_method()");
     }
 }