blocks|key|4101748|text|整数是自动装入箱内的，所以你可以这样做|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4101749|if+(count+>+0)+{
++++....+
}|code-block|syntax|javascript|4101750|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|$]]

Integers are autounboxed, so you can just do 

<pre><code>if (count &gt; 0) {
 .... 
}
</code></pre>

blocks|key|4101828|text|出于两个原因，最好避免不必要的自动装箱。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4101829|首先，它比int+<+int慢一点，因为你(有时)要创建一个额外的对象；|offset|length|style|CODE|4101830|void+doSomethingWith(Integer+integerObject){+...
++int+i+=+1000;
++doSomethingWith(i);//gets+compiled+into+doSomethingWith(Integer.valueOf(i));|code-block|syntax|javascript|4101831|更大的问题是隐藏的自动装箱可以隐藏异常：|4101832|void+doSomethingWith+(Integer+count){
++if+(count>0)++//+gets+compiled+into+count.intValue()>0|4101833|使用null调用此方法将抛出NullPointerException。|4101834|java中原语和包装器对象之间的分离总是被描述为为了速度而拼凑起来的东西。自动装箱几乎隐藏了这一点，但并不完全是-它更干净，只是为了跟踪类型。因此，如果你有一个整数对象，你可以直接调用compare()或intValue()，如果你有原语，只需直接检查值。|4101835|entityMap^0|0|5|9|0|0|0|0|2|4|E|K|0|2K|9|2U|A|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|X|8|@$D|Y|E|Z|F|G]]|9|@]|A|$]]|$1|H|3|I|5|J|7|10|8|@]|9|@]|A|$K|L]]|$1|M|3|N|5|6|7|11|8|@]|9|@]|A|$]]|$1|O|3|P|5|J|7|12|8|@]|9|@]|A|$K|L]]|$1|Q|3|R|5|6|7|13|8|@$D|14|E|15|F|G]|$D|16|E|17|F|G]]|9|@]|A|$]]|$1|S|3|T|5|6|7|18|8|@$D|19|E|1A|F|G]|$D|1B|E|1C|F|G]]|9|@]|A|$]]|$1|U|3|-4|5|6|7|1D|8|@]|9|@]|A|$]]]|V|$]]

It's better to avoid unnecessary autoboxing for 2 reasons. 

For one thing, it's a bit slower than <code>int &lt; int</code>, as you're (sometimes) creating an extra object;

<pre><code>void doSomethingWith(Integer integerObject){ ...
 int i = 1000;
 doSomethingWith(i);//gets compiled into doSomethingWith(Integer.valueOf(i));
</code></pre>

The bigger issue is that hidden autoboxing can hide exceptions:

<pre><code>void doSomethingWith (Integer count){
 if (count&gt;0) // gets compiled into count.intValue()&gt;0
</code></pre>

Calling this method with <code>null</code> will throw a <code>NullPointerException</code>.

The split between primitives and wrapper objects in java was always described as a kludge for speed. Autoboxing almost hides this, but not quite - it's cleaner just to keep track of the type. So if you've got an Integer object, you can just call <code>compare()</code> or <code>intValue()</code>, and if you've got the primitive just check the value directly.

blocks|key|1305676|text|您还可以使用equals：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1305677|+Integer+a+=+0;

+if+(a.equals(0))+{
+++++//+a+==+0
+}|code-block|syntax|javascript|1305678|相当于：|1305679|+if+(a.intValue()+==+0)+{
+++++//+a+==+0
+}|1305680|还有：|1305681|+if+(a+==+0)+{

+}|1305682|(+Java编译器自动添加intValue())|offset|length|style|BOLD|1305683|注意，自动装箱/自动装箱可能会带来很大的开销(特别是在循环内部)。|1305684|entityMap^0|0|0|0|0|0|0|D|8|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|Z|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|10|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|11|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|12|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|13|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|14|8|@$Q|15|R|16|S|T]]|9|@]|A|$]]|$1|U|3|V|5|6|7|17|8|@]|9|@]|A|$]]|$1|W|3|-4|5|6|7|18|8|@]|9|@]|A|$]]]|X|$]]

You can also use equals:

<pre><code> Integer a = 0;

 if (a.equals(0)) {
 // a == 0
 }
</code></pre>

which is equivalent to:

<pre><code> if (a.intValue() == 0) {
 // a == 0
 }
</code></pre>

and also:

<pre><code> if (a == 0) {

 }
</code></pre>

(the Java compiler automatically adds intValue())

Note that autoboxing/autounboxing can introduce a significant overhead (especially inside loops).

blocks|key|4101788|text|尽管您肯定可以在Integer实例上使用compareTo方法，但在读取代码时并不清楚，因此您可能应该避免这样做。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|4101789|Java允许您使用自动装箱(请参阅http://java.sun.com/j2se/1.5.0/docs/guide/language/autoboxing.html)来直接与整数进行比较，因此您可以这样做：|4101790|if+(count+>+0)+{+}|code-block|syntax|javascript|4101791|并且Integer实例count将自动转换为int以进行比较。|4101792|如果你对此理解有困难，请查看上面的链接，或者想象它是这样做的：|4101793|if+(count.intValue()+>+0)+{+}|4101794|entityMap|0|LINK|mutability|MUTABLE|url|http://java.sun.com/j2se/1.5.0/docs/guide/language/autoboxing.html^0|K|9|0|H|1U|0|0|0|2|7|B|5|M|3|0|0|0^^$0|@$1|2|3|4|5|6|7|10|8|@$9|11|A|12|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|13|8|@]|D|@$9|14|A|15|1|16]]|E|$]]|$1|H|3|I|5|J|7|17|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|18|8|@$9|19|A|1A|B|C]|$9|1B|A|1C|B|C]|$9|1D|A|1E|B|C]]|D|@]|E|$]]|$1|O|3|P|5|6|7|1F|8|@]|D|@]|E|$]]|$1|Q|3|R|5|J|7|1G|8|@]|D|@]|E|$K|L]]|$1|S|3|-4|5|6|7|1H|8|@]|D|@]|E|$]]]|T|$U|$5|V|W|X|E|$Y|Z]]]]

Although you could certainly use the <code>compareTo</code> method on an Integer instance, it's not clear when reading the code, so you should probably avoid doing so.

Java allows you to use autoboxing (see <a href="http://java.sun.com/j2se/1.5.0/docs/guide/language/autoboxing.html" rel="nofollow noreferrer">http://java.sun.com/j2se/1.5.0/docs/guide/language/autoboxing.html</a>) to compare directly with an int, so you can do:

<pre><code>if (count &gt; 0) { }
</code></pre>

And the <code>Integer</code> instance <code>count</code> gets automatically converted to an <code>int</code> for the comparison.

If you're having trouble understanding this, check out the link above, or imagine it's doing this:

<pre><code>if (count.intValue() &gt; 0) { }
</code></pre>

blocks|key|1305694|text|另一件要注意的事情是，如果第二个值是另一个整数对象而不是文字'0'，'==‘操作符将比较对象指针，不会自动拆箱。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1305695|即：|1305696|Integer+a+=+new+Integer(0);+++
Integer+b+=+new+Integer(0);+++
int+c+=+0;

boolean+isSame_EqOperator+=+(a==b);+//false!
boolean+isSame_EqMethod+=+(a.equals(b));+//true
boolean+isSame_EqAutoUnbox+=+((a==c)+&&+(a.equals(c));+//also+true,+because+of+auto-unbox

//Note:+for+initializing+a+and+b,+the+Integer+constructor+
//+is+called+explicitly+to+avoid+integer+object+caching+
//+for+the+purpose+of+the+example.
//+Calling+it+explicitly+ensures+each+integer+is+created+
//+as+a+separate+object+as+intended.
//+Edited+in+response+to+comment+by+@nolith|code-block|syntax|javascript|1305697|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

One more thing to watch out for is if the second value was another Integer object instead of a literal '0', the '==' operator compares the object pointers and will not auto-unbox.

ie:

<pre><code>Integer a = new Integer(0); 
Integer b = new Integer(0); 
int c = 0;

boolean isSame_EqOperator = (a==b); //false!
boolean isSame_EqMethod = (a.equals(b)); //true
boolean isSame_EqAutoUnbox = ((a==c) &amp;&amp; (a.equals(c)); //also true, because of auto-unbox

//Note: for initializing a and b, the Integer constructor 
// is called explicitly to avoid integer object caching 
// for the purpose of the example.
// Calling it explicitly ensures each integer is created 
// as a separate object as intended.
// Edited in response to comment by @nolith
</code></pre>

blocks|key|883856|text|好吧，我可能会迟到，但我想分享一些东西：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|883857|给定输入:+System.out.println(isGreaterThanZero(-1))；|883858|public+static+boolean+isGreaterThanZero(Integer+value)+{
++++return+value+==+null?false:value.compareTo(0)+>+0;
}|code-block|syntax|javascript|883859|返回false|offset|length|style|BOLD|883860|public+static+boolean+isGreaterThanZero(Integer+value)+{
++++return+value+==+null?false:value.intValue()+>+0;
}|883861|返回true，所以我认为在你的例子中'compareTo‘会更准确。|883862|entityMap^0|0|0|0|2|5|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|V|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|W|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|X|8|@$K|Y|L|Z|M|N]]|9|@]|A|$]]|$1|O|3|P|5|F|7|10|8|@]|9|@]|A|$G|H]]|$1|Q|3|R|5|6|7|11|8|@]|9|@]|A|$]]|$1|S|3|-4|5|6|7|12|8|@]|9|@]|A|$]]]|T|$]]

well i might be late on this but i would like to share something:

Given the input:
 System.out.println(isGreaterThanZero(-1));

<pre><code>public static boolean isGreaterThanZero(Integer value) {
 return value == null?false:value.compareTo(0) &gt; 0;
}
</code></pre>

Returns false

<pre><code>public static boolean isGreaterThanZero(Integer value) {
 return value == null?false:value.intValue() &gt; 0;
}
</code></pre>

Returns true
So i think in yourcase 'compareTo' will be more accurate.

I'm a newbie Java coder and I just read a variable of an integer class can be described three different ways in the API. I have the following code: 

<pre><code>if (count.compareTo(0)) { 
 System.out.println(out_table);
 count++;
 }
</code></pre>

This is inside a loop and just outputs <code>out_table</code>. 
My goal is to figure out how to see if the value in integer <code>count &gt; 0</code>. 

I realize the <code>count.compare(0)</code> is the correct way? or is it <code>count.equals(0)</code>? 

I know the <code>count == 0</code> is incorrect. Is this right? Is there a value comparison operator where its just <code>count=0</code>?

Integer value comparison

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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我是一个新手Java程序员，我只是读了一个整数类的变量，在API中可以用三种不同的方式来描述。我有以下代码：if (count.compareTo(0)) {             System.out.println(out_table);            count++;    }这是在一个循环中，只是输出out_table。我的目标是弄清楚如何查看整型count > 0中的值。我知道

问整数值比较
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