blocks|key|23053|text|整数对象是不同的。它不同于基本的int类型。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|23054|请看这个答案：How+to+properly+compare+two+Integers+in+Java?|offset|length|23055|i+!=+j部分是真的，而您期望它是假的。|style|CODE|23056|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/1514910/when-comparing-two-integers-in-java-does-auto-unboxing-occur^0|0|7|19|0|0|0|6|0^^$0|@$1|2|3|4|5|6|7|R|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|S|8|@]|9|@$D|T|E|U|1|V]]|A|$]]|$1|F|3|G|5|6|7|W|8|@$D|X|E|Y|H|I]]|9|@]|A|$]]|$1|J|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|K|$L|$5|M|N|O|A|$P|Q]]]]

The integer objects are different. It is different from the basic int type.

See this answer: <a href="https://stackoverflow.com/questions/1514910/when-comparing-two-integers-in-java-does-auto-unboxing-occur">How to properly compare two Integers in Java?</a>

The <code>i != j</code> part is true, which you were expecting to be false.

blocks|key|23087|text|循环没有结束，因为您的条件为真(i+!=+j为真，因为有两个不同的对象，请改用Integer.valueOf+)，并且循环内部的值不会改变，因此您的条件永远保持为真。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|23088|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|$]]

The loop is not ending because your condition is true( i != j is true because there are 2 different objects, use Integer.valueOf instead) and inside the loop the values are not changing so your condition remains true forever.

blocks|key|239648|text|可能是因为'i‘和'j’都是对象，对象比较和对象引用比较不一样。请考虑使用!i.equals(j)而不是i!=j|type|unstyled|depth|inlineStyleRanges|entityRanges|data|239649|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|$]]

Perhaps the reason is that both 'i' and 'j' are objects, and object comparison is not the same as object reference comparison. Please consider using !i.equals(j) instead of i!=j

blocks|key|239685|text|程序会继续显示相同的i值，因为您既没有递增也没有递减i或j的值。for中的条件总是计算为true，因此它是一个无限循环。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|239686|entityMap^0|A|1|Q|1|S|1|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|O|8|@]|D|@]|E|$]]]|G|$]]

The program keeps on displaying the same value of <code>i</code> because you aren't incrementing or decrementing either the value of <code>i</code> or <code>j</code>. The condition in the for always keeps evaluating to true, so it is an infinite loop.

blocks|key|23264|text|你必须知道它在&&+this和this+&中有一点不同，当你使用&，当第一个条件为真时，它检查第二个条件，如果它为假，那么它不检查第三个条件，因为在&运算符中，如果一个条件为假，所有的语句都为假，如果使用%7C%7C，那么如果它看起来为真，那么在你的代码中返回真，因为i和j相等，第一个条件和第二个条件为真，那么在第三个条件中，它将为假，因为它们相等，而条件为假。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|23265|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|$]]

you have to know its a bit different in &amp;&amp; this and this &amp; when you use &amp;&amp; then when first condition is true then it check second condition if its false then it not checked third condition because in &amp; operator if one condition is false all of the statement is false if use || then if it see true then it return true in your code because i and j is equal first and second condition are true then in third condition it will be false because they are equal and while condition is false .

blocks|key|23295|text|整数对象是不同的。它不同于基本的int类型。所以你可以这样做。你所做的仅仅是比较对象，结果当然是真的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|23296|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|$]]

The integer objects are different. It is different from the basic int type.
so you can just do like that. what you do it's just compare the object and of course the result is true.

blocks|key|239833|text|我们首先要了解两种不同的情况，|type|unstyled|depth|inlineStyleRanges|entityRanges|data|239834|案例1：|239835|++++++++Integer+i+=+new+Integer(10);
++++++++Integer+j+=+new+Integer(10);

++++++++System.out.println((i<=j+&&+j<=i+&&+i!=j));
++++++++System.out.println(i!=j);|code-block|syntax|javascript|239836|案例2：|239837|++++++++Integer+i+=+10;
++++++++Integer+j+=+10;

++++++++System.out.println((i<=j+&&+j<=i+&&+i==j));
++++++++System.out.println(i==j);|239838|两者都是不同的，因为|239839|在情况1中：i!=j将为true，因为两者都引用了堆中的两个不同的对象，并且不能相同。但|offset|length|style|CODE|239840|在情况2中：i==j将是true，因为这两个10都是整数字面值，并且Java维护pool+for+Integer+literals，它的值为(-128+<=+X+<=+127)。因此，在本例中，10<=127结果为真，因此两者都将引用相同的对象。|239841|entityMap^0|0|0|0|0|0|0|6|4|C|4|0|6|4|C|4|14|P|1Y|I|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]]|$1|M|3|N|5|6|7|13|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|14|8|@$Q|15|R|16|S|T]|$Q|17|R|18|S|T]]|9|@]|A|$]]|$1|U|3|V|5|6|7|19|8|@$Q|1A|R|1B|S|T]|$Q|1C|R|1D|S|T]|$Q|1E|R|1F|S|T]|$Q|1G|R|1H|S|T]]|9|@]|A|$]]|$1|W|3|-4|5|6|7|1I|8|@]|9|@]|A|$]]]|X|$]]

There are two different cases which we have to understand first,

case 1:

<pre><code> Integer i = new Integer(10);
 Integer j = new Integer(10);

 System.out.println((i&lt;=j &amp;&amp; j&lt;=i &amp;&amp; i!=j));
 System.out.println(i!=j);
</code></pre>

case 2:

<pre><code> Integer i = 10;
 Integer j = 10;

 System.out.println((i&lt;=j &amp;&amp; j&lt;=i &amp;&amp; i==j));
 System.out.println(i==j);
</code></pre>

both are different, as 

in case 1: <code>i!=j</code> will be <code>true</code> because both referencing to two different object in heap and can't be same. But

in case 2: <code>i==j</code> will be <code>true</code> because both 10 are integer literals and Java maintains <code>pool for Integer literals</code> which have value <code>(-128 &lt;= X &lt;= 127)</code>. So, in this case 10&lt;=127 results true, So both will have reference to same object.

I have written a piece of Java code which is running in an infinite loop.

Below is the code:

<pre><code>public class TestProgram {
 public static void main(String[] args){
 Integer i = new Integer(0);
 Integer j = new Integer(0);

 while(i&lt;=j &amp;&amp; j&lt;=i &amp;&amp; i!=j){
 System.out.println(i);
 }
 }
}
</code></pre>

In the code above, while seeing the condition in the <code>while</code> loop, at first it looks like that program will not go inside the <code>while</code> loop. But actually it is an infinite loop and keeps printing the value.

What is happening here?

Why does (i<=j && j<=i && i!=j) evaluate to TRUE?

Java

我已经写了一段Java代码，它在无限循环中运行。代码如下：public class TestProgram {    public static void main(String[] args){        Integer i = new Integer(0);        Integer j = new Int...

问为什么(i<=j && j<=i && i!=j)的计算结果为真？
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