在 Java 中不使用“new"关键字声明数组 [英] Declaring arrays without using the 'new' keyword in Java

问题描述

以下两个声明有什么区别吗?

Is there any difference between the following two declarations?

int arr[] = new int [5];

和

int arr1[] = {1,2,3,4,5};

arr1 是声明在栈上还是堆上?

Is arr1 declared on stack or on the heap?

推荐答案

有一个明显的区别，一个全零，另一个包含 [1..5].

There is the obvious difference that one has all zeros, and the other contains [1..5].

但这是唯一的区别.两者都是 5 个元素的 int 数组，它们的分配方式相同.用大括号声明只是语法上的方便，没有 new.

But that's the only difference. Both are 5-element int arrays, both are allocated in the same way. It is mere syntactic convenience to declare with the braces and no new.

注意这种形式只能在声明数组时使用:

Note that this form can only be used when the array is declared:

int[] blah = {}

但不是

int[] blah;
blah = {};

或

return {};

对象(数组就是对象)在堆上分配.

Objects (arrays are objects) are allocated on the heap.

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