Java父类强制转换子类原则 原创

我们知道Java中子类转换成父类是没有问题的，那父类可以转换成子类吗？ 

复制javapublic class ObjectConvert {

    public static void main(String[] args) {
        test1();
        test2();
    }

    private static void test1() {
        Fruit fruit1 = new Fruit();
        Apple apple1 = new Apple();
        apple1 = (Apple) fruit1;
    }

    private static void test2() {
        Fruit fruit1 = new Apple();
        Apple apple1 = new Apple();
        apple1 = (Apple) fruit1;
    }

    static class Fruit {}
    static class Apple extends Fruit {}
}
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