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private的构造方法可以通过Class.newInstance调用呢

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拉宫有个布达

#1 Created at ... [Delete] [Delete and Lock User]

通过Class.newInstance()可以创建类实例，它的局限是：只能调用public的无参数构造方法。带参数的构造方法，或者非public的构造方法都无法通过Class.newInstance()被调用。

public class Aclass {        private Aclass(){            System.out.println("Aclass私有构造方法");        }    public static void main(String[] args) throws Exception {        Class cls = Aclass.class;        System.out.println(cls.newInstance());    }}

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Aclass私有构造方法
Aclass@610455d6

老师,private的构造方法可以通过Class.newInstance调用呢?

The__Wolf

#2 Created at ... [Delete] [Delete and Lock User]

他意思是你得用Class.newInstance().Aclass()这样才叫调用把，估计是调不起来

廖雪峰

#3 Created at ... [Delete] [Delete and Lock User]

我不知道你是怎么运行的，private构造方法绝对会抛出IllegalAccessException

Jared·Golden·Spirit

#4 Created at ... [Delete] [Delete and Lock User]

你这个是Aclass类自身的main里调用private 构造方法的，用其他类去newInstance就会报java.lang.IllegalAccessException，其实就是private的作用域的原理。

Joker.fu_95

#5 Created at ... [Delete] [Delete and Lock User]

这个方式可以

Constructor cn = cls.getDeclaredConstructor();cn.setAccessible(true);cn.newInstance();
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