sample5_2.java

封装

class Person{
    private int age;//年龄
    public void setAge(int newAge){
   if(newAge>0){age=newAge;}
   else{System.out.println("错误！年龄要大于0！");}
   }
   public int getAge() {return age;}	
}
	
public class Sample5_2{
   public static void main(String[] args){
   Person pn=new Person();
   pn.setAge(6);
   System.out.println(pn.getAge());
   }
}