AccessControl.java

package p2;

class Derived extends p1.Original{
    void Access(){
        
        System.out.println("**** 不同包的子类 ****");
        //System.out.println("friendly member"+n_friendly);
        //不能访问
        //System.out.println("private member "+n_private);
        //不能访问
        System.out.println("protected member"+n_protected);
        //子类可以访问父类
        System.out.println("public member "+n_public);

        p1.Original o = new p1.Original();
        System.out.println("**** 访问在不同包中的父类 ****");
        // System.out.println("friendly member"+o.n_friendly);
        //不能访问
        //System.out.println("private member "+o.n_private);
        //不能访问
        //System.out.println("protected member"+o.n_protected);
        //不能访问
        System.out.println("public member "+o.n_public);
    
    }
}

class AnotherPackageClass{
    void Access(){
        p1.Original o = new p1.Original();
        System.out.println("****  另一包中的其他类 ****");
         // System.out.println("friendly member"+o.n_friendly);
        //不能访问
        //System.out.println("private member "+o.n_private);
        //不能访问
        //System.out.println("protected member"+o.n_protected);
        //不能访问
        System.out.println("public member "+o.n_public);
    }
}

public class AccessControl{
    public static void main(String args[]){
        Derived d  = new Derived();
        d.Access();
        AnotherPackageClass a = new AnotherPackageClass();
        a.Access();
    }
}