小编geo*_*e24的帖子

考虑下面的两个简单的Java类:

第一个例子

class Computer {
    Computer() {
        System.out.println("Constructor of Computer class.");
    }
    void On() {
        System.out.println("PC turning on...");
    }
    void working() {
        System.out.println("PC working...");
    }
    void Off() {
        System.out.println("PC shuting down...");
    }
    public static void main(String[] args) {
        Computer my = new Computer();
        Laptop your = new Laptop();
        my.On();
        my.working();
        your.On();
        your.working();
        my.Off();
        your.Off();
   }
}

第二个例子

class Laptop {
    Laptop() {
        System.out.println("Constructor of Laptop class.");
    }
    void On() {
        System.out.println("Laptop turning on...");
    }
    void working() {
        System.out.println("Laptop working...");
    } …