(小白问题) Java 关于 this 的指向问题 - V2EX
V2EX = way to explore
V2EX 是一个关于分享和探索的地方
现在注册
已注册用户请  登录
rabbbit
V2EX    问与答

(小白问题) Java 关于 this 的指向问题

  •  
  •   rabbbit 2020-10-12 21:16:03 +08:00 1743 次点击
    这是一个创建于 1837 天前的主题,其中的信息可能已经有所发展或是发生改变。

    这个 this 到底指向谁, 为什么 s.getName() 输出 foo, 而 s.name 输出 bar.
    我以为两个都结果都应该是 bar,是哪里搞错了?

    class Person { public String name = "foo"; public String getName() { return this.name; } } class Student extends Person { public String name = "bar"; } public class Hello { public static void main(String[] args) { Student s = new Student(); System.out.println(s.getName()); // foo System.out.println(s.name); // bar } } 
    4 条回复    2020-10-13 14:02:03 +08:00
    yumenawei
        1
    yumenawei  
       2020-10-12 21:49:57 +08:00   1
    帮顶~
    billlee
        2
    billlee  
       2020-10-12 21:54:16 +08:00   1
    字段没有多态性,this.name 取的是编译期 this 变量所属类的 name, 对于 Person::getName 来说,this 是 Person, this.name 是 "foo".
    对于 main 中的 s.name 来说,s 是 Student, s.name 是 "bar".
    itechify
        3
    itechify  
    PRO
       2020-10-12 23:32:21 +08:00 via Android   1
    多态针对接口(行为,方法),属性没有多态
    dushe
        4
    dushe  
       2020-10-13 14:02:03 +08:00
    this 指向最近的对象
    关于     帮助文档     自助推广系统     博客     API     FAQ     Solana     2608 人在线   最高记录 6679       Select Language
    创意工作者们的社区
    World is powered by solitude
    VERSION: 3.9.8.5 25ms UTC 15:05 PVG 23:05 LAX 08:05 JFK 11:05
    Do have faith in what you're doing.
    ubao msn snddm index pchome yahoo rakuten mypaper meadowduck bidyahoo youbao zxmzxm asda bnvcg cvbfg dfscv mmhjk xxddc yybgb zznbn ccubao uaitu acv GXCV ET GDG YH FG BCVB FJFH CBRE CBC GDG ET54 WRWR RWER WREW WRWER RWER SDG EW SF DSFSF fbbs ubao fhd dfg ewr dg df ewwr ewwr et ruyut utut dfg fgd gdfgt etg dfgt dfgd ert4 gd fgg wr 235 wer3 we vsdf sdf gdf ert xcv sdf rwer hfd dfg cvb rwf afb dfh jgh bmn lgh rty gfds cxv xcv xcs vdas fdf fgd cv sdf tert sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf shasha9178 shasha9178 shasha9178 shasha9178 shasha9178 liflif2 liflif2 liflif2 liflif2 liflif2 liblib3 liblib3 liblib3 liblib3 liblib3 zhazha444 zhazha444 zhazha444 zhazha444 zhazha444 dende5 dende denden denden2 denden21 fenfen9 fenf619 fen619 fenfe9 fe619 sdf sdf sdf sdf sdf zhazh90 zhazh0 zhaa50 zha90 zh590 zho zhoz zhozh zhozho zhozho2 lislis lls95 lili95 lils5 liss9 sdf0ty987 sdft876 sdft9876 sdf09876 sd0t9876 sdf0ty98 sdf0976 sdf0ty986 sdf0ty96 sdf0t76 sdf0876 df0ty98 sf0t876 sd0ty76 sdy76 sdf76 sdf0t76 sdf0ty9 sdf0ty98 sdf0ty987 sdf0ty98 sdf6676 sdf876 sd876 sd876 sdf6 sdf6 sdf9876 sdf0t sdf06 sdf0ty9776 sdf0ty9776 sdf0ty76 sdf8876 sdf0t sd6 sdf06 s688876 sd688 sdf86