publicclassA{publicvoidshowA(){
System.out.println("A 类");}}publicclassB{publicvoidshowB(){
System.out.println("B 类");}}publicclassC{publicvoidshowC(){
System.out.println("C 类");}}// 门面,调用这几个类,需要组合这几个类publicclassFade{private A a =newA();private B b =newB();private C c=newC();publicvoidneed_1(){this.a.showA();this.b.showB();}publicvoidneed_2(){this.a.showA();this.c.showC();}}// 测试publicclassMain{publicstaticvoidmain(String[] args){
Fade fade =newFade();
fade.need_1();// A 类 B 类
fade.need_2();// A 类 C 类}}