门面模式结构图
示例代码:
public class FacadeTest {
public static void main(String[] args) {
Facade facade = new Facade();
facade.doWork();
}
// 子系统A
static class SystemA{
public void work(){
System.out.println("系统A准备工作......");
}
}
// 子系统B
static class SystemB{
public void work(){
System.out.println("系统B准备工作......");
}
}
// 子系统C
static class SystemC{
public void work(){
System.out.println("系统C准备工作......");
}
}
// 外观角色
static class Facade{
private SystemA systemA = new SystemA();
private SystemB systemB = new SystemB();
private SystemC systemC = new SystemC();
// 对外接口
public void doWork(){
systemA.work();
systemB.work();
systemC.work();
}
}
}
总结:
优点:简化了调用过程,松散耦合,遵循迪米特法则;
缺点:不符合开闭原则,某种情况下可能违背单一职责原则.
原文:https://www.cnblogs.com/wqlken/p/14651204.html