package com.mediator.theory;public class TestMediator{    public static void main(String[] args)    {        Mediator mediator=new MediatorImpl();        mediator.handle("rent");        mediator.handle("sale");    }}package com.mediator.theory;public interface Mediator{    public void handle(String content);}package com.mediator.theory;public class MediatorImpl implements Mediator{    private HouseOwner owner1;    private HouseOwner owner2;        public MediatorImpl()    {        owner1=new HouseRent();        owner2=new HouseSale();    }    @Override    public void handle(String content)    {        if("rent".equals(content))        {            owner1.action();        }        if("sale".equals(content))        {            owner2.action();        }    }}package com.mediator.theory;public interface HouseOwner{    public void action();}package com.mediator.theory;public class HouseRent implements HouseOwner{    @Override    public void action()    {        System.out.println("客户来了需要租房");    }}package com.mediator.theory;public class HouseSale implements HouseOwner{    @Override    public void action()    {        System.out.println("客户来了需要卖房");    }}