Java - null instanceof Object evaluates to both true and false 在Java中，null instanceof Object同时评估为true和false

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Java - null instanceof Object evaluates to both true and false 在Java中，null instanceof Object同时评估为true和false

当我编译和运行这段代码时：

public class Testing {
    public static void main(String... args) {
        Object obj = null;
        if (obj instanceof Object) {
            System.out.println("returned true"); 
        } else {
            System.out.println("returned false"); 
        }
        System.out.println(" " + obj instanceof Object);
    }
}

我在命令行上得到以下结果：

C:\Users\xxxxxx\Desktop>java Testing
returned false
true

"null instanceof someType"不应该总是返回false吗？

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