模拟手机与SIM卡的组合关系

要求：

           SIM卡类负责创建SIM卡；

           Phone类负责创建手机；

          手机可以组合一个SIM卡；

          手机可以更换其中的SIM卡。

public class SIM {long number;long getNumber() {return number;}void setNumber(long number) {this.number=number;}}

public class Phone {SIM sim=new SIM();public SIM getSim() {return sim;}public void setSim(SIM sim) {this.sim=sim;}public long number() {return sim.getNumber();}}

public class TestPhone {public static void main(String[] args) {// TODO Auto-generated method stubSIM sim=new SIM();          //构造对象sim.setNumber(12671328);Phone phone=new Phone();phone.setSim(sim);System.out.println("手机号码是:"+phone.number());SIM sim1=new SIM();         //构造新对象sim1.setNumber(18724570);phone.setSim(sim1);         //更换SIM卡System.out.println("手机号码是:"+phone.number());}}