Java练习题

class Frock{
    private static int currentNum=100000;
    private int serialNumber;

    int getSerialNumber() {
        return serialNumber;
    }

    public Frock() {
     serialNumber = getNextNum();
    }

    public static int getNextNum(){
        currentNum+=100;
        return  currentNum;
    }
}
class TestFrock{
    public static void main(String[] args) {
        System.out.println(Frock.getNextNum());
        System.out.println(Frock.getNextNum());
        Frock f1=new Frock();
        System.out.println(f1.getSerialNumber() );
        Frock f2=new Frock();
        System.out.println(f2.getSerialNumber() );
        Frock f3=new Frock();
        System.out.println(f3.getSerialNumber() );
    }
}

结果：