blocks|key|678642|text|根据编译器的不同，它应该映射到相同的字节代码。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|678643|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Depending upon the compiler, it should map to the same byte code.

blocks|key|678857|text|JVM会找到最好的方法来生成字节码，在这两种情况下都应该做same.So，我认为这没有区别。而(True)只是更漂亮而已。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|678858|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

JVM will find the best way to make bytecode and in both cases should do the same.So I think there's no difference. while(true) is just prettier.

blocks|key|678908|text|在功能上没有区别。与在循环体中运行的任何指令相比，由于字节码的差异而获得或损失的任何效率都可能微不足道。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|678909|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Functionally there is no difference. Any efficiency gained or lost by a difference in bytecode will likely be insignificant compared to any instruction you would run in the body of the loop.

blocks|key|678952|text|在Oracle+Java+7上，您会得到相同的字节代码。你不能从原始文件中使用的字节代码中辨别出来。哪一个是最好的是品味问题。我使用while(true)|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|678953|entityMap^0|1U|B|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|$]]

On Oracle Java 7 you get the same byte code. You cannot tell from the byte code which was using in the original. Which is best is a matter of taste. I use <code>while(true)</code>

blocks|key|463881|text|你自己决定用哪一个。因为它们等同于编译器。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|463882|创建文件：|463883|//+first+test
public+class+Test+{
++++public+static+void+main(String[]+args)+{
++++++++while+(true)+{
++++++++++++System.out.println("Hi");
++++++++}
++++}
}|code-block|syntax|javascript|463884|编译：|463885|javac+-g:none+Test.java
rename+Test.class+Test1.class|463886|463887|//+second+test
public+class+Test+{
++++public+static+void+main(String[]+args)+{
++++++++for+(;;)+{
++++++++++++System.out.println("Hi");
++++++++}
++++}
}|463888|463889|javac+-g:none+Test.java
mv+Test.class+Test2.class|463890|比较：|463891|diff+-s+Test1.class+Test2.class
Files+Test1.class+and+Test2.class+are+identical|463892|entityMap^0|0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Z|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|10|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|11|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|12|8|@]|9|@]|A|$G|H]]|$1|M|3|C|5|6|7|13|8|@]|9|@]|A|$]]|$1|N|3|O|5|F|7|14|8|@]|9|@]|A|$G|H]]|$1|P|3|J|5|6|7|15|8|@]|9|@]|A|$]]|$1|Q|3|R|5|F|7|16|8|@]|9|@]|A|$G|H]]|$1|S|3|T|5|6|7|17|8|@]|9|@]|A|$]]|$1|U|3|V|5|F|7|18|8|@]|9|@]|A|$G|H]]|$1|W|3|-4|5|6|7|19|8|@]|9|@]|A|$]]]|X|$]]

It's up to you which one to use. Cause they are equals to compiler.

create file:

<pre><code>// first test
public class Test {
 public static void main(String[] args) {
 while (true) {
 System.out.println("Hi");
 }
 }
}
</code></pre>

compile:

<pre><code>javac -g:none Test.java
rename Test.class Test1.class
</code></pre>

create file:

<pre><code>// second test
public class Test {
 public static void main(String[] args) {
 for (;;) {
 System.out.println("Hi");
 }
 }
}
</code></pre>

compile:

<pre><code>javac -g:none Test.java
mv Test.class Test2.class
</code></pre>

compare:

<pre><code>diff -s Test1.class Test2.class
Files Test1.class and Test2.class are identical
</code></pre>

blocks|key|679039|text|只是解析器所需的时间不同，两个不同的表达式包括不同数量的要解析的令牌，但是计算时间差异非常小，并且两种情况下编译的字节码是相同的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|679040|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Only the difference is required time for the parser, the two distinct expressions include different number of tokens to be parsed however the computation time difference is very low and the compiled bytecode is the same for two cases.

What is the difference between a standard <code>while(true)</code> loop and <code>for(;;)</code>?

Is there any, or will both be mapped to the same bytecode after compiling?

Java: for(;;) vs. while(true)

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Java

标准while(true)循环和for(;;)之间的区别是什么有没有，或者在编译后两者都会映射到同一字节码？

问Java: for(;;) vs. while(true)
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