Java 限制子类访问的方法分析

class Person
{
   // 在这里将属性封装
   private String name;
   private int age;
}
class Student extends Person
{
   // 在这里访问父类中被封装的属性
   public void setVar()
   {
      super.name="李四";
      super.age=25;
      name = "张叁";
      age = 25;
   }
}
public class RestrictVisit
{
   public static void main( String[] args )
   {
      new Student().setVar();
   }
}

class Person{
  // 在这里将属性封装
  private String name;
  private int age;
  Person(String name, int age)
  {
    this.name = name;
    this.age = age;
  }
  // 在这里访问父类中被封装的属性
  void setVar(String name, int age)
  {
    this.name = name;
    this.age = age;
  }
  
  void print()
  {
    System.out.println("I am : " + name + ", I am : " + age + " years old");
  }
}
class Student extends Person
{
  Student(String name, int age)
  {
    super(name, age);
  }
  /*  
  void Test () // 在这里尝试访问父类中被封装的属性
  {
    System.out.println("I am : " + name + ", I am : " + age + " years old");
  }
  */
  
  /*
  void print()
  {
    System.out.println("I am : " + name + ", I am : " + age + " years old");
  }
  */
  
}
public class RestrictVisit2
{
  public static void main( String[] args )
  {
    Student s = new Student("Jack",30);
    s.print();
    s.setVar("Tom", 25);
    s.print();
    // s.Test();
  }
}