package Main;
public class Private {
 private int a;
 private int b;
 Protected (){
  this.a=1;
  this.b=2;
  //a和b只能在Private类中调用
 }
 private void set(){
  System.out.println(""+a+""+b+"\n");
 }
 void Print(){
  this.set();
  //只能在这里用；
 }
}

package Main;
import Protected.*;
public class Main {
 public static void main(String args[]){
  Protected jkl=new Protected();
  jkl.Print();
  //调用jkl父类的protect方法 
  Frindly prot =new Frindly();
  System.out.println(prot.a);
  //在Main类中调用友好型的变量 
  prot.set();
  //在Main类中调用友好型的方法
 }
}
package Main;
public class Frindly {
 int a,b,c,d;
 Frindly(){
  a=b=c=d=1;
 }
 void set (){
  System.out.print(""+a+" "+b+"\n");
 }
}
package Main;
public class Protectedfather{
 protected int a;
 private int b;
 protected Protectedfather (){
  this.a=1;
  this.b=2;
  //a和b只能在Protected中调用
 }
 private void set(){
  System.out.println(""+a+""+b+"\n");
 }
 protected void Print(){
  this.set();
  //只能在这里用；
 }
}
package Protected;
import Main.*;
public class Protected extends Protectedfather{
 public Protected(){
  super();
  //在另一个包中调用里父类中的protect构造方法 
  super.a=12;
  //调用父类的protect变量
 }
}

package Main;
import Public.*;
public class Main {
 public static void main(String args[]){
  int a;
  Public p=new Public();
  //调用public类中的public方法 
  a=p.a;
  //调用Public类中的public变量 
  p.set();
 }
}
package Public;
public class Public {
 public int a=12;
 public void set (){
  System.out.println("OK\n");
 }
}