对于父类的私有属性，子类是从哪里访问到的详解编程语言

其实也是牵扯到子类继承父类时，父类的private属性在子类中是什么样的问题。

根据JAVA官方的定义：

A subclass does not inherit the private members of its parent class. However, if the superclass has public or protected methods for accessing its private fields, these can also be used by the subclass.

A nested class has access to all the private members of its enclosing class—both fields and methods. Therefore, a public or protected nested class inherited by a subclass has indirect access to all of the private members of the superclass.

子类是无法继承父类的private成员的，但是在子类对象的内存里有没有父类的private成员呢？来看以下的代码：

package cn.haiyisoft3; 
 
public class ExtendsDemo02 { 
 
	/** 
	 * @param args 
	 */ 
	public static void main(String[] args) { 
		// TODO Auto-generated method stub 
		// 验证子类能否访问父类中的private属性或者方法 
		// 或者说继承？ 
		child ch = new child(); 
		ch.setage(10); 
		ch.name = "xiaomim"; 
		System.out.println(ch); 
		System.out.println(ch.getage()); 
 
	} 
 
} 
 
class person_private { 
	private int age; 
	String name; 
 
	public void setage(int age) { 
		this.age = age; 
	} 
 
	public int getage() { 
		System.out.println(this); 
		return this.age; 
	} 
 
} 
 
class child extends person_private { 
	void cry() { 
		System.out.println("wowo"); 
	} 
} 

其运行结果如下：

[email protected] 
[email protected] 
10 

这说明this和ch指向的是同一个对象，也就是说子类调用的自己实例对象内存空间的父类私有属性age。

所以，我认为子类实例空间中是有父类的私有成员的，但是有不代表继承，只有能直接使用才说明子类继承了父类。