封装
在面向对象程式设计方法中，封装是指—种将抽象性函式接口的实现细节部分包装、隐藏起来的方法
封装可以被认为是一个保护屏障，防止该类的代码和数据被外部类定义的代码随机访问
要访问该类的代码和数据，必须通过严格的接口控制
封装最主要的功能在于我们能修改自己的实现代码，而不用修改那些调用我们代码的程序片段,适当的封装可以让程式码更容易理解与维护，也加强了程式码的安全性
实现Java封装的步骤
1.修改属性的可见性来限制对属性的访问，如设置成private
2.对每个值属性提供对外的公共方法访问，用于对私有属性的访问，如设置get,set方法
接口
接口是抽象方法的集合，用interface来声明，一个类通过继承接口，来继承接口的抽象方法
类描述对象的属性和方法，接口包含类要实现的方法
一个实现接口的类，必须得实现接口内的所有方法
接口与类的区别
接口不能用于实例化对象，没有构造方法，所有的方法都是抽象方法，不能包含成员变量，
接口不是被类继承了，而是要被类实现，接口支持多继承
接口和抽象类的区别
抽象类中的方法有方法体，接口中的方法没有
抽象类的成员变量可以是各种类型的，接口中的成员变量只能是public static final类型的
接口中不能含有静态代码块和静态代码
一个类只能继承一个抽象类，而一个类可以实现多个接口
封装示例
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"page": "",
"real_total_results": "1276155",
"total_results": 6000,
"pagecount": 100,
"products_total": "",
"list_count": "",
"page_size": "60",
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"num_iid": "10024538221803",
"detail_url": "https://item.jd.com/10024538221803.html",
"title": "珂米莎外套女2020新款秋冬大衣女韩版两面穿宽松大码女装连帽短款外套女士卫衣女休闲上衣胖妹妹夹克风衣 豆沙红 XL（115-125斤）",
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"sample_id": "",
"post_fee": "",
"area": "",
"seller": "珂米莎服饰旗舰店"
},
{
"num_iid": "56188926756",
"detail_url": "https://item.jd.com/56188926756.html",
"title": "帝黛外套女2021春秋新品女装短款休闲韩版风衣女士小香风卫衣工装夹克大码女装棒球学生上衣 雾霾蓝【双面穿】 注意【请选择需要的款式及正确的...",
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"seller": "帝黛旗舰店"
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"num_iid": "56189137600",
"detail_url": "https://item.jd.com/56189137600.html",
"title": "帝黛品牌外套女2021春秋新品女装夹克中长款休闲斗篷韩版运动风衣时尚女士卫衣小香风服饰大码棒球服上衣 黑色【1919款】 注意【请选择需要的款式...",
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"seller": "帝黛旗舰店"
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"num_iid": "10026369237393",
"detail_url": "https://item.jd.com/10026369237393.html",
"title": "珠珊连衣裙女装2021初春季工装套装女轻熟风时尚小个子洋气显瘦子 军绿 S",
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"seller": "珠珊服饰旗舰店"
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"num_iid": "10020493224847",
"detail_url": "https://item.jd.com/10020493224847.html",
"title": "五个橘子短外套女2021春季新款女装韩版外套女中长款宽松大码呢子大衣女时尚洋气上衣小个子毛呢外套秋 卡其色 L(105-120斤)",
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"seller": "五个橘子服饰旗舰店"
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"num_iid": "10026510819788",
"detail_url": "https://item.jd.com/10026510819788.html",
"title": "格素凡 卫衣女春季2021新款韩版时尚连帽三件套跑步休闲运动服套装女宽松大码春装百搭马甲外套女装潮 卡其女-L 建议体重98-113斤",
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"seller": "格素凡宁天天专卖店"
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"detail_url": "https://item.jd.com/10026460211981.html",
"title": "单蜜风衣女装2021春秋新款韩版宽松显瘦小个子中长款风衣小香风外套上衣女米色 XL",
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"seller": "单蜜旗舰店"
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{
"num_iid": "10026585998888",
"detail_url": "https://item.jd.com/10026585998888.html",
"title": "单蜜长袖连衣裙女装2021春季新款韩版宽松显瘦休闲中长款小个子打底裙子女潮 图片色 M【建议105-115斤】",
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"seller": "单蜜服饰官方旗舰店"
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"detail_url": "https://item.jd.com/10026557183750.html",
"title": "蓝玑卫衣女装新品2021春秋季新款韩版宽松连帽时尚拼接小个子上衣小香风短外套女潮 深灰色 XL【推荐120-140斤左右】",
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"seller": "蓝玑旗舰店"
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"detail_url": "https://item.jd.com/10026511013315.html",
"title": "麦潮尚 卫衣女春季2021新款韩版时尚束腿裤两件套跑步休闲运动服套装宽松大码春季女百搭外套洋气女装潮 黑色女-L 建议体重98-113斤",
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"seller": "麦潮尚旗舰店"
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{
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"detail_url": "https://item.jd.com/10026511174922.html",
"title": "伊卡茵 卫衣女春季2021新款韩版时尚两件套圆领大码跑步休闲运动服套装宽松外套春装女宽松洋气女装潮 黑色女-L 建议体重98-113斤",
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"price": 238,
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"seller": "大唛服饰专营店"
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{
"num_iid": "10025091904145",
"detail_url": "https://item.jd.com/10025091904145.html",
"title": "淳咪娜 品牌针织衫女开衫2020秋冬新品欧货大牌毛衣外套女加厚麻花连帽牛角扣设计中长款粗线大毛衣网红 咖啡色【品牌保证】 XL - 大码 126-168斤",
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"seller": "淳咪娜旗舰店"
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{
"num_iid": "10026491215986",
"detail_url": "https://item.jd.
