2-封装性

package com.example;

/**
 * Created by Y on 16/4/13.
 */
public class Person {
    private int age;
    private String name;
    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        if (age>=0 && age<=150) {
            this.age = age;
        }
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
    public void tell(){
        System.out.println("年龄是：" + getAge() + "姓名是：" + getName());
    }

}

package com.example;


public class MyClass {
    public static void  main(String[] args){
    //封装性：保护某些属性和方法不被外部所看见.为属性和方法进行封装是通过关键字PRIVATE声明的.实现该属性的SET和GET方法为外部所访问
        Person per = new Person();
        per.setName("xiaoyu");
        per.setAge(20);
        per.tell();
    }
}