习题（转载，）

public class fulei {
public fulei()
{
System.out.println("欢迎使用海尔");
}
public String Pinpai;
public String Xinghao;
public fulei(String pinpai, String xinghao)
{
this.Pinpai = pinpai;
this.Xinghao = xinghao;
System.out.println(Pinpai+"饮水机\n"+"型号为"+Xinghao);
}
int t = 0;
public void reshui(int 时间)
{
t = 时间;
if(t > 15&&t<20)
{
System.out.println("保温");
}
else
{
System.out.println("加热");
}
}
public void xiaodu(int 时间1)
{
t = 时间1;
if(t >= 20)
{
System.out.println("消毒");
}
}
}

public class zilei1 extends fulei
{
public zilei1 (String Pinpai, String Xinghao)
{
super (Pinpai, Xinghao);
}
public zilei1()
{
String Pinpai = "美的";
String Xinghao = "HB350";
System.out.println("我是"+Pinpai+Xinghao);
}
int t;
public void xiaodu(int t)
{
if(t > 65)
{
System.out.println("正在消毒");
}
}
}

public static void main(String[] args) {
// TODO Auto-generated method stub
fulei ysj1 = new fulei();
fulei ysj = new fulei("Haier", "GB125");
ysj.reshui(6);
ysj.xiaodu(70);
ysj.reshui(16);

zilei1 ysj2 = new zilei1();
ysj2.xiaodu(70);

//向上转型调用方法
fulei ysj3 = new zilei1();
ysj3.xiaodu(80);
}

}