中介模式:用一个中介对象来封装一系列的对象交互。中介者使各对象不需要显式地相互引用,从而使其耦合松散,而且可以独立得改变它们之间的交互。
//国家 public abstract class Country { protected UnitedNations mediator; public Country(UnitedNations mediator) { this.mediator = mediator; } }
//联合国机构 public abstract class UnitedNations { public abstract void Declare(String message,Country colleague); }
//伊拉克 public class Iraq extends Country{ public Iraq(UnitedNations mediator) { super(mediator); } //声明 public void Declare(String message) { mediator.Declare(message, this); } //获得消息 public void getMessage(String message) { System.out.println("伊拉克获得对方消息:" + message); } }
//美国 public class USA extends Country{ public USA(UnitedNations mediator) { super(mediator); } //声明 public void Declare(String message) { mediator.Declare(message, this); } //获得消息 public void getMessage(String message) { System.out.println("美国获得对方的信息:" + message); } }
public class UnitedNationsSecurityCouncil extends UnitedNations{ USA colleague1; Iraq colleague2; @Override public void Declare(String message, Country colleague) { if(colleague == colleague1) { colleague2.getMessage(message); }else { colleague1.getMessage(message); } } }public class TestMediator { public static void main(String[] args) { UnitedNationsSecurityCouncil UNSC = new UnitedNationsSecurityCouncil(); USA c1 = new USA(UNSC); Iraq c2 = new Iraq(UNSC); UNSC.colleague1 = c1; UNSC.colleague2 = c2; c1.Declare("不准研发,否则发动战争"); c2.Declare("我们没有,也不怕被打"); } }