Java protected 关键字

定义和用法

protected 关键字是用于属性、方法和构造函数的访问修饰符，使它们在同一包和子类中可访问。

相关页面

教程：Java 修饰符

实例

Student 子类访问带有 protected 属性的 Person 类：

class Person {
  protected String fname = "Bill";
  protected String lname = "Gates";
  protected String email = "bill@doe.com";
  protected int age = 24;
}

class Student extends Person {
  private int graduationYear = 2024;
  public static void main(String[] args) {
    Student myObj = new Student();
    System.out.println("名字：" + myObj.fname + " " + myObj.lname);
    System.out.println("电邮：" + myObj.email);
    System.out.println("年龄：" + myObj.age);
    System.out.println("毕业年：" + myObj.graduationYear);
  }
}

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