编辑代码

package p1;
class Protection
{
    int n =1;
    private int n_pri = 2;
    protected int n_pro = 3;
    public int n_pub = 4;
    public Protection()
    {
        System.out.println("base constructor");
        System.out.println("n = " + n);
        System.out.println("n_pri = " + n_pri);
        System.out.println("n_pro = " + n_pro);
        System.out.println("n_pub = " + n_pub);
    }
}