blocks|key|2604242|text|在您的代码中，您将在内存中分配一个由10个整数组成的数组，并获取对它的引用。在for循环中，您只需迭代数组中的每一项，对于所有项，最初的值将为0。在迭代数组元素时，每一项的值都将存储在for循环中声明的变量i中。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2604243|entityMap^0|2V|1|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

In your code, you allocate an array of 10 integers in the memory and obtain a reference to it. In the for-loop you simply iterate over every item in the array, which initially will be 0 for all the items. The value of every item will be stored in the variable <code>i</code> declared in your for-loop as you iterate the array elements.

blocks|key|2604251|text|该循环等同于：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2604252|for(int+j+=+0;+j+<+number.length;+j%2B%2B)+{
++int+i+=+number[j];
++...
}|code-block|syntax|javascript|2604253|其中j是不与正常用户标识符冲突的内部生成的引用。|2604254|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

The loop is equivalent to:

<pre><code>for(int j = 0; j &lt; number.length; j++) {
 int i = number[j];
 ...
}
</code></pre>

where j is an internally generated reference that does not conflict with normal user identifiers.

blocks|key|10955|text|数组上的for+each本质上是这个构造上的“糖”：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|10956|for(int+i+=+0;i<number.length;i%2B%2B)
{++
}|code-block|syntax|javascript|10957|我想这是作为语言的一种构造提供的，这样人们就可以在以旧方式迭代的结构上使用增强的for循环。|10958|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

The for each over arrays is essentially "sugar" over this construct: 

<pre><code>for(int i = 0;i&lt;number.length;i++)
{ 
}
</code></pre>

I would imagine this was provided as a construct of the language so that people could use the enhanced for loop over a structure that was iterated over in the old way.

blocks|key|1923536|text|这相当于：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1923537|for(int+x+=+0;+x+<+number.length;+x%2B%2B)+{
++int+i+=+number[x];
}|code-block|syntax|javascript|1923538|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

this is equivalent to:

<pre><code>for(int x = 0; x &lt; number.length; x++) {
 int i = number[x];
}
</code></pre>

blocks|key|1917157|text|这相当于：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1917158|final+int+len+=+number.length;
for(int+j+=+0;+j+<+len;+j%2B%2B)+{
++int+i+=+number[j];
}|code-block|syntax|javascript|1917159|请注意，forEach不会在每个循环中计算.length。这也可能被JVM消除，但特别是在集合的情况下，其中一些可能会使用|1917160|for(int+j+=+0;+j+<+collection.size();+j%2B%2B)+{|1917161|它使(微小的)差别更快|1917162|int+len+=+collection.size()
for(int+j+=+0;+j+<+len;+j%2B%2B)+{|1917163|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

This is the equivalent to:

<pre><code>final int len = number.length;
for(int j = 0; j &lt; len; j++) {
 int i = number[j];
}
</code></pre>

Note that the forEach will not evaluate the .length in each loop.
This might be also be eliminated by the JVM, but especially in case of collections,
where some would use 

<pre><code>for(int j = 0; j &lt; collection.size(); j++) {
</code></pre>

it makes a (small) difference to the faster

<pre><code>int len = collection.size()
for(int j = 0; j &lt; len; j++) {
</code></pre>

blocks|key|4717250|text|有点晚了，但现在就到了。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4717251|编译器知道是否将for-each循环语句用于集合或数组。|4717252|如果用于收集，编译器会使用Iterator将for-each循环转换为等效的for循环。|offset|length|style|CODE|4717253|如果用于数组，编译器会使用索引变量将for-each循环转换为等效的for循环。|4717254|Here+is+a+description+at+oracle.com|4717255|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.oracle.com/javase/1.5.0/docs/guide/language/foreach.html^0|0|0|D|8|0|0|0|Z|0|0^^$0|@$1|2|3|4|5|6|7|V|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|W|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|X|8|@$F|Y|G|Z|H|I]]|9|@]|A|$]]|$1|J|3|K|5|6|7|10|8|@]|9|@]|A|$]]|$1|L|3|M|5|6|7|11|8|@]|9|@$F|12|G|13|1|14]]|A|$]]|$1|N|3|-4|5|6|7|15|8|@]|9|@]|A|$]]]|O|$P|$5|Q|R|S|A|$T|U]]]]

A bit late, but here it is.

The compiler knows if you are using the for-each loop statement for a collection or for an array.

If used for collection,
the compiler translates the for-each loop to the equivalent for loop using an <code>Iterator</code>.

If used for an array,
the compiler translates the for-each loop to the equivalent for loop using an index variable.

<a href="https://docs.oracle.com/javase/1.5.0/docs/guide/language/foreach.html" rel="noreferrer">Here is a description at oracle.com</a>

blocks|key|4717257|text|如果使用Java8，则可以使用IntStream.range(1,4)。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|4717258|entityMap^0|F|K|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

<code>IntStream.range(1,4)</code> can be used, if using java 8.

I understand that new for each loop works with Iterable and arrays, but I don't know what goes behind the scenes when working with arrays. 

Can anyone help me understand this? Thanks in advance.

<pre><code>int[] number = new int[10];

for(int i: number) {

}
</code></pre>

How does primitive array work with new for each loop in Java?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我知道new for each循环适用于Iterable和数组，但我不知道使用数组时幕后会发生什么。有人能帮我理解这个吗？提前谢谢。int[] number = new int[10];for(int i: number) {}

问在Java中，基本数组是如何处理new for each循环的？
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问在Java中，基本数组是如何处理new for each循环的？EN