练习练习

import java.util.Scanner;//包含包

public class ex1

{

public static void main(String args[])//程序入口

{

Phone phone = new Phone();//建一个手机

phone.logo = "SONY";//弄上个牌子

phone.battery.power = 100;//给电池弄上100电

Scanner reader = new Scanner(System.in);//为输入XXX做准备

int command = 0;//为选择用

boolean sign = true;//循环标志

System.out.printf("输入1听音乐\n输入2充电\n输入3显示电量\n");

while(sign)

{

command = reader.nextInt();//输入...

switch (command)

{

case 1:

System.out.println("听音乐");

phone.music();//播放音乐

phone.showpower();//显示电量

break;

case 2:

System.out.println("充电");

phone.showpower();

phone.inpower();//充电

break;

case 3:

System.out.println("显示电量");

phone.showpower();

break;

case 4:

sign = false;//结束循环，结束程序。

break;

default://缺省

break;

}

}

}

}

class Phone//电话类

{

String logo;//牌子

Battery battery = new Battery();//给电话加上电池

Music music = new Music();//电话的音乐

void music()

{

if(music.have())//没有音乐是不能播放音乐的

{

if(battery.outpower())//播放音乐就会使用电池

System.out.println("music......" + music.song);

else

System.out.println("battery low");

}

else

System.out.println("song null");

}

void inpower()//电池充电

{

if(battery.inpower())

System.out.println("电量已充满");

else

showpower();

}

void showpower()//显示电量

{

System.out.println("当前电量" + battery.power);

}

}

class Battery//电池类

{

String logo;

short power;

boolean inpower()//充电

{

power += 10;

if(power >= 100)

{

power = 100;

return true;

}

else

{

return false;

}

}

boolean outpower()//使用电量

{

if(power >= 10)

{

power -= 10;

return true;

}

else

{

power = 0;

return false;

}

}

}

class Music

{

String song = "song1";

void list()//音乐清单，【没空去实现选择了】

{

System.out.println("song1");

System.out.println("song2");

System.out.println("song3");

System.out.println("song4");

}

boolean have()//是否有音乐

{

if(song == "null")

return false;

else

return true;

}

boolean down(short num)//下载音乐

{

switch (num)

{

case 1:

song = "song1";

break;

case 2:

song = "song2";

break;

case 3:

song = "song3";

break;

case 4:

song = "song4";

break;

default:

return false;

}

return true;

}

}