中介者模式

中介者模式的定义为：Define an object that encapsulates how a set of objects
interact.Mediator promotes loose coupling by keeping objects from referring to each other
explicitly,and it lets you vary their interaction independently.（用一个中介对象封装一系列的对象
交互，中介者使各对象不需要显示地相互作用，从而使其耦合松散，而且可以独立地改变它

们之间的交互。）

public abstract class Mediator {
//定义同事类
protected ConcreteColleague1 c1;
protected ConcreteColleague2 c2;
//通过getter/setter方法把同事类注入进来
public ConcreteColleague1 getC1() {
return c1;
}
public void setC1(ConcreteColleague1 c1) {
this.c1 = c1;
}
public ConcreteColleague2 getC2() {
return c2;
}
public void setC2(ConcreteColleague2 c2) {
this.c2 = c2;
}
//中介者模式的业务逻辑
public abstract void doSomething1();
public abstract void doSomething2();

}

中介者模式的优点就是减少类间的依赖，把原有的一对多的依赖变成了一对一的依赖，同事类只依赖中介者，减少了依赖，当然同时也降低了类间的耦合。