blocks|key|3136462|text|Math.pow被声明为|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3136463|public+static+double+pow​(double+a,+double+b)|code-block|syntax|javascript|3136464|所以我们要处理的是替身。Math.pow(2,63)是"2.0d+%5E+63.0d“(power，不是eor)。由于double总共为64位，因此更改低于最高有效位的60个奇数位的值不会改变该值。所以Math.pow(2,63)+==+Math.pow(2,63)+-+1，也就是(double)9223372036854775807L。|3136465|在第一个if中隐含地进行隐式强制转换。|3136466|++++if((double)9223372036854775807L+<+Math.pow(2.0d,63.0d))+{
++++++++System.out.println("True");++++++++++++++++++++++++++++//+DOES+NOT+GET+PRINTED
++++}|3136467|<的左边和右边都是9.223372036854776E18，所以是false。|3136468|entityMap^0|0|8|0|0|C|E|S|C|1L|6|2R|10|3V|S|0|4|2|0|0|0|1|9|K|X|5|0^^$0|@$1|2|3|4|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|X|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|Y|8|@$9|Z|A|10|B|C]|$9|11|A|12|B|C]|$9|13|A|14|B|C]|$9|15|A|16|B|C]|$9|17|A|18|B|C]]|D|@]|E|$]]|$1|M|3|N|5|6|7|19|8|@$9|1A|A|1B|B|C]]|D|@]|E|$]]|$1|O|3|P|5|H|7|1C|8|@]|D|@]|E|$I|J]]|$1|Q|3|R|5|6|7|1D|8|@$9|1E|A|1F|B|C]|$9|1G|A|1H|B|C]|$9|1I|A|1J|B|C]]|D|@]|E|$]]|$1|S|3|-4|5|6|7|1K|8|@]|D|@]|E|$]]]|T|$]]

<code>Math.pow</code> is declared as

<pre><code>public static double pow​(double a, double b)
</code></pre>

So we are dealing with doubles. <code>Math.pow(2,63)</code> is "<code>2.0d ^ 63.0d</code>" (power, not eor). As <code>double</code> is 64 bits in total, changing the value 60 odd bits below the most significant bit will not change the value. So <code>Math.pow(2,63) == Math.pow(2,63) - 1</code>, which is also <code>(double)9223372036854775807L</code>.

Making the implicits casts implicit in the first <code>if</code>.

<pre><code> if((double)9223372036854775807L &lt; Math.pow(2.0d,63.0d)) {
 System.out.println("True"); // DOES NOT GET PRINTED
 }
</code></pre>

Both left and right side of <code>&lt;</code> are <code>9.223372036854776E18</code>, so <code>false</code>.

blocks|key|2969358|text|以下代码将帮助您理解它：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2969359|public+class+Main+{
++++public+static+void+main(String[]+args)+{
++++++++System.out.println("Long.MAX_VALUE+is+"+%2B+Long.MAX_VALUE);
++++++++System.out.println("Math.pow(2,+63)+is+"+%2B+Math.pow(2,+63));
++++++++System.out.println("Math.pow(2,+63)+-+1+is+"+%2B+(Math.pow(2,+63)+-+1));
++++++++System.out.println("(long)Math.pow(2,+63)+is+"+%2B+(long)+Math.pow(2,+63));
++++++++System.out.println("(long)(Math.pow(2,+63)+-+1)+is+"+%2B+(long)+(Math.pow(2,+63)+-+1));

++++++++if+(9223372036854775807L+<+Math.pow(2,+63))+{
++++++++++++System.out.println("9223372036854775807L+<+Math.pow(2,+63)");
++++++++}

++++++++if+(9223372036854775807L+<=+Math.pow(2,+63))+{
++++++++++++System.out.println("9223372036854775807L+<=+Math.pow(2,+63)");
++++++++}

++++++++if+(9223372036854775807L+<=+Math.pow(2,+63)+-+1)+{
++++++++++++System.out.println("9223372036854775807L+<=+Math.pow(2,+63)+-+1");
++++++++}

++++++++if+(9223372036854775807L+<+(long)+Math.pow(2,+63))+{
++++++++++++System.out.println("9223372036854775807L+<+(long)Math.pow(2,+63)");
++++++++}

++++++++if+(9223372036854775807L+<=+(long)+Math.pow(2,+63))+{
++++++++++++System.out.println("9223372036854775807L+<=+(long)Math.pow(2,+63)");
++++++++}

++++++++if+(9223372036854775807L+<=+(long)+Math.pow(2,+63)+-+1)+{
++++++++++++System.out.println("9223372036854775807L+<=+(long)Math.pow(2,+63)+-+1");
++++++++}

++++++++if+(9223372036854775807L+<=+(long)+(Math.pow(2,+63)+-+1))+{
++++++++++++System.out.println("9223372036854775807L+<=+(long)(Math.pow(2,+63)+-+1)");
++++++++}
++++}
}|code-block|syntax|javascript|2969360|输出：|offset|length|style|BOLD|2969361|Long.MAX_VALUE+is+9223372036854775807
Math.pow(2,+63)+is+9.223372036854776E18
Math.pow(2,+63)+-+1+is+9.223372036854776E18
(long)Math.pow(2,+63)+is+9223372036854775807
(long)(Math.pow(2,+63)+-+1)+is+9223372036854775807
9223372036854775807L+<=+Math.pow(2,+63)
9223372036854775807L+<=+Math.pow(2,+63)+-+1
9223372036854775807L+<=+(long)Math.pow(2,+63)
9223372036854775807L+<=+(long)(Math.pow(2,+63)+-+1)|2969362|entityMap^0|0|0|0|3|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]]|$1|G|3|H|5|6|7|S|8|@$I|T|J|U|K|L]]|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|$]]

The following code will help you understand it:

<pre><code>public class Main {
 public static void main(String[] args) {
 System.out.println("Long.MAX_VALUE is " + Long.MAX_VALUE);
 System.out.println("Math.pow(2, 63) is " + Math.pow(2, 63));
 System.out.println("Math.pow(2, 63) - 1 is " + (Math.pow(2, 63) - 1));
 System.out.println("(long)Math.pow(2, 63) is " + (long) Math.pow(2, 63));
 System.out.println("(long)(Math.pow(2, 63) - 1) is " + (long) (Math.pow(2, 63) - 1));

 if (9223372036854775807L &lt; Math.pow(2, 63)) {
 System.out.println("9223372036854775807L &lt; Math.pow(2, 63)");
 }

 if (9223372036854775807L &lt;= Math.pow(2, 63)) {
 System.out.println("9223372036854775807L &lt;= Math.pow(2, 63)");
 }

 if (9223372036854775807L &lt;= Math.pow(2, 63) - 1) {
 System.out.println("9223372036854775807L &lt;= Math.pow(2, 63) - 1");
 }

 if (9223372036854775807L &lt; (long) Math.pow(2, 63)) {
 System.out.println("9223372036854775807L &lt; (long)Math.pow(2, 63)");
 }

 if (9223372036854775807L &lt;= (long) Math.pow(2, 63)) {
 System.out.println("9223372036854775807L &lt;= (long)Math.pow(2, 63)");
 }

 if (9223372036854775807L &lt;= (long) Math.pow(2, 63) - 1) {
 System.out.println("9223372036854775807L &lt;= (long)Math.pow(2, 63) - 1");
 }

 if (9223372036854775807L &lt;= (long) (Math.pow(2, 63) - 1)) {
 System.out.println("9223372036854775807L &lt;= (long)(Math.pow(2, 63) - 1)");
 }
 }
}
</code></pre>

Output:

<pre><code>Long.MAX_VALUE is 9223372036854775807
Math.pow(2, 63) is 9.223372036854776E18
Math.pow(2, 63) - 1 is 9.223372036854776E18
(long)Math.pow(2, 63) is 9223372036854775807
(long)(Math.pow(2, 63) - 1) is 9223372036854775807
9223372036854775807L &lt;= Math.pow(2, 63)
9223372036854775807L &lt;= Math.pow(2, 63) - 1
9223372036854775807L &lt;= (long)Math.pow(2, 63)
9223372036854775807L &lt;= (long)(Math.pow(2, 63) - 1)
</code></pre>

When I run the following code in JVM, I am unable to understand why it behaves like this. 
As per my understanding, <code>&lt; x</code> operator should go till <code>x-1</code>. 

<pre><code> public class LongQuestion {

 public static void main(String[] args) {

 if(9223372036854775807L &lt; Math.pow(2,63)) {
 System.out.println("True"); // DOES NOT GET PRINTED
 }

 if(9223372036854775807L &lt;= Math.pow(2,63) - 1 ) {
 System.out.println("Also True"); // THIS GETS PRINTED
 }

 }

}
</code></pre>

I want to understand why Java behaves like this.

Java: difference between < and <= for long integer for 9223372036854775807L

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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当我在JVM中运行以下代码时，我无法理解它为什么会这样。根据我的理解，< x运算符应该转到x-1。 public class LongQuestion { public static void main(String[] args) { if(9223372036854775807L < Math.p...

问Java: 9223372036854775807L的长整型的<和<=的区别
EN

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问Java: 9223372036854775807L的长整型的<和<=的区别EN