声明函数时初始化vars(Java VS C ++) [英] initalizing vars when declaring functions (Java VS C++)

问题描述

大家好，

我是java的新手，我想弄清楚在声明一个函数时是否可以为变量赋值.

这是一些解释 (Correct me if i''m wrong)

在C ++中，我们可以这样写:

Hi all,

I''m new to java and i''m trying to figure out if we could assign values to variables when declaring a function.

Here is some explanation (Correct me if i''m wrong)

in C++ We could write:

class Humain 
{
public:
    String nom;
    int age;
public:
    Humain(int age, String name): age(age), name(name){}
}

我想知道我们是否可以像这样用Java编写.

PS:我浏览了许多网站，并且所有网站都使用了以下内容

I''m wondering if we could write in java like that.

PS: i looked in many web sites and all used as below

Humain(int age, String name){
   this.age = age;
   this. name = name;
}

谢谢.

Thank you.

推荐答案

与C ++不同，您可以在类中指定初始值，但不能使用初始化程序列表.我不知道该怎么做才能提高性能，但我认为编译器会删除冗余的初始化.

干杯，

灰

PS:您是否有Arnold，Gosling和Holmes撰写的"Java编程语言"的副本?如果不抓取副本，它将得到类似这样的答案. (顺便说一句，这就是我得到这个问题的答案).

Unlike C++ you can specify initial values in your class but you can''t use an initialiser list. Quite what that does for performance I don''t know but I assume the compiler removes redundant initialisation.

Cheers,

Ash

PS: Have you got a copy of "The Java Programming Language" by Arnold, Gosling and Holmes? If not grab a copy, it''s got answers like this in it. (That''s where I got the answer to this question BTW).

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