例如,

class Person {
    private String name;

    public String getName () {
        return this.name;
    }

    Person(String name) {
        this.name = name;
    }
}

public class Student extends Person {

    Student(String name) {
        super(name);
    }
    
    public String getStudentName() {
        return this.getName(); // works
        // "return this.name;" doesn't work, and the error is "The field Person.name is not visible"

    }
}

public class Main {
    public static void main(String[] args) {
        Student s = new Student("Bill");

        String name = s.getName(); // works
        // "String name = s.name;" doesn't work, and the error is "The field Person.name is not visible"

        System.out.println(name);
    }
}

It would seem that a subclass does inherit the private fields in that these very fields are utilized in the inner workings of the subclass (philosophically speaking). A subclass, in its constructor, calls the superclass constructor. The superclass private fields are obviously inherited by the subclass calling the superclass constructor if the superclass constructor has initialized these fields in its constructor. That's just an example. But of course without accessor methods the subclass cannot access the superclass private fields (it's like not being able to pop the back panel of an iPhone to take the battery out to reset the phone... but the battery is still there).

PS 我遇到的关于继承的许多定义之一是: “继承——一种编程技术，允许派生类扩展基类的功能，继承其所有的STATE(重点是我的)和行为。”

私有字段即使不能被子类访问，也是父类的继承状态。

我们可以简单地声明，当父类被继承时，父类的私有成员实际上成为子类的私有成员，并且不能被进一步继承或子类的对象不可访问。

好吧，这是一个非常有趣的问题，我研究了很多，得出的结论是，父类的私有成员确实在子类的对象中可用(但不可访问)。为了证明这一点，这里是一个带有父类和子类的示例代码，我正在将子类对象写入txt文件，并在文件中读取名为“bhavesh”的私有成员，因此证明它确实在子类中可用，但由于访问修饰符而不可访问。

import java.io.Serializable;
public class ParentClass implements Serializable {
public ParentClass() {

}

public int a=32131,b,c;

private int bhavesh=5555,rr,weq,refw;
}

import java.io.*;
import java.io.Serializable;
public class ChildClass extends ParentClass{
public ChildClass() {
super();
}

public static void main(String[] args) {
ChildClass childObj = new ChildClass();
ObjectOutputStream oos;
try {
        oos = new ObjectOutputStream(new FileOutputStream("C:\\MyData1.txt"));
        oos.writeObject(childObj); //Writing child class object and not parent class object
        System.out.println("Writing complete !");
    } catch (IOException e) {
    }


}
}

打开MyData1.txt，搜索名为“bhavesh”的私有成员。请告诉我你们的想法。

我将用代码演示这个概念。子类实际上继承了父类的私有变量。唯一的问题是他们不能访问 子对象，除非您为私有变量提供公共getter和setter 在超级班。

考虑包转储中的两个类。子扩展父。

如果我没记错的话，内存中的子对象由两个区域组成。一个是父部分，另一个是子部分。子程序可以访问私有文件 节只能通过父类中的公共方法在其父类的代码中调用。

这样想。波拉特的父亲博尔托克有一个装有10万美元的保险箱。他不想共享他的“私有”变量保险箱。所以，他没有提供保险箱的钥匙。波拉特继承了保险箱。但是，如果他连门都打不开，那又有什么用呢?要是他的 爸爸提供了钥匙。

父母,

package Dump;

public class Parent {

    private String reallyHidden;
    private String notReallyHidden;

    public String getNotReallyHidden() {
        return notReallyHidden;
    }

    public void setNotReallyHidden(String notReallyHidden) {
        this.notReallyHidden = notReallyHidden;
    }

}//Parent

孩子,

package Dump;

public class Child extends Parent {

    private String childOnly;

    public String getChildOnly() {
        return childOnly;
    }

    public void setChildOnly(String childOnly) {
        this.childOnly = childOnly;
    }

    public static void main(String [] args){

        System.out.println("Testing...");
        Child c1 = new Child();
        c1.setChildOnly("childOnly");
        c1.setNotReallyHidden("notReallyHidden");

        //Attempting to access parent's reallyHidden
            c1.reallyHidden;//Does not even compile

    }//main

}//Child

我必须回答，Java中的私有字段是继承的。请允许我演示一下:

public class Foo {

    private int x; // This is the private field.

    public Foo() {
        x = 0; // Sets int x to 0.
    }

    //The following methods are declared "final" so that they can't be overridden.
    public final void update() { x++; } // Increments x by 1.
    public final int getX() { return x; } // Returns the x value.

}


public class Bar extends Foo {

    public Bar() {

        super(); // Because this extends a class with a constructor, it is required to run before anything else.

        update(); //Runs the inherited update() method twice
        update();
        System.out.println(getX()); // Prints the inherited "x" int.

    }

}

如果你在一个程序中运行Bar Bar = new Bar();，那么你总是会在输出框中看到数字“2”。由于整数“x”被update()和getX()方法封装，因此可以证明该整数是继承的。

令人困惑的是，因为不能直接访问整数“x”，所以人们认为它不是继承的。然而，类中的每一个非静态的东西，无论是字段还是方法，都是继承的。