设计模式之外观模式

1类图

2java示例

public class Test {

public static void main(String[] args) {
Facade facade=new Facade();
facade.methodA();
System.out.println("-------------------");
facade.methodB();
}

}

public class Facade {
private SubSystemA systemA;
private SubSystemB systemB;
private SubSystemC systemC;

public Facade(){
this.systemA=new SubSystemA();
this.systemB=new SubSystemB();
this.systemC=new SubSystemC();
}

public void methodA(){
this.systemA.doSomething();
this.systemB.doSomething();
}

public void methodB(){
this.systemA.doSomething();
this.systemC.doSomething();
}

}

public class SubSystemA {
public void doSomething(){
System.out.println("调用了子系统A");
}
}

public class SubSystemB {
public void doSomething(){
System.out.println("调用了子系统B");
}
}

public class SubSystemC {
public void doSomething(){
System.out.println("调用了子系统C");
}
}