Java中Integer和int之间的区别

Dear 丶 2023-10-05 19:23 52阅读 0赞

在Java中，**int是原始数据类型，而Integer是Wrapper类**。

*  int，作为原始数据类型具有较小的灵活性。我们只能在其中存储整数的二进制值。
 *  由于Integer是int数据类型的[包装器类][Link 1]，因此它在存储，转换和操作int数据方面为我们提供了更大的灵活性。
 *  Integer是一个类，因此可以调用该类中定义的各种内置方法。与其他任何引用（对象）类型一样，Integer类型的变量存储对Integer对象的引用。

public class IntegerAndint {
    	public static void main(String[] args) {
    
    		Integer a = new Integer(1);
    		Integer b = new Integer(1);
    		int c = 1;
    		int d = 1;
    		System.out.println(a == b);// false
    		System.out.println(a == c);// true
    		System.out.println(c == d);// true
    		System.out.println(a.equals(b));// true
    	}
    
    }

输出：

false  
true  
true  
true

**例子：**

//有效
    整数n = 20;
    //有效
    整数n = 45;
    
    //有效
    Integer.parseInt（“ 10”）;
    // 无效
    int.parseInt（“ 10”）;

**差异要点：**

1.  强制**转换为字符串变量：**我们不能直接或什至通过强制转换将字符串值（仅包含整数）分配给int变量。但是，我们可以使用Integer（String）构造函数将String分配给Integer类型的对象。我们甚至可以使用parseInt（String）将String文字转换为int值。
    
    *filter\_none*
    
    *编辑*
    
    *play\_arrow*
    
    *亮度\_4*
    
    <table style="width:607.844px;"> 
     <tbody> 
      <tr> 
       <td style="text-align:left;vertical-align:baseline;width:430px;"> 
        <div style="margin-left:0px;"> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>// Java program to illustrate&nbsp; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>// difference between </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>// int and Integer&nbsp; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;</code>&nbsp;</span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>public</code> <code>class</code> <code>Main { </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>public</code> <code>static</code> <code>void</code> <code>main(String args[]) </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>{ </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;</code>&nbsp;</span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>Integer a = </code><code>new</code> <code>Integer(</code><code>"123"</code><code>); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// Casting not possible </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// int a = (int)"123"; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// Casting not possible </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// int c="123"; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;</code>&nbsp;</span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// Casting possible using methods </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// from Integer Wrapper class </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>int</code> <code>b = Integer.parseInt(</code><code>"123"</code><code>); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>System.out.print(a + </code><code>new</code> <code>Float(</code><code>"10.1"</code><code>)); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>} </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>} </code></span> 
         </div> 
        </div> </td> 
      </tr> 
     </tbody> 
    </table>
    
    **输出：**
    
        133.1
2.  **将值直接转换为其他基数：**我们可以分别使用toBinaryString（），toOctalString（）或toHexString（）将存储在Integer类中的整数值直接转换为Binary，Octal或Hexadecimal格式。在int类型的变量中这是不可能的。
    
    *filter\_none*
    
    *编辑*
    
    *play\_arrow*
    
    *亮度\_4*
    
    <table style="width:607.844px;"> 
     <tbody> 
      <tr> 
       <td style="text-align:left;vertical-align:baseline;width:497px;"> 
        <div style="margin-left:0px;"> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>// Java program to illustrate&nbsp; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>// difference between </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>// int and Integer&nbsp; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;</code>&nbsp;</span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>public</code> <code>class</code> <code>Main { </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>public</code> <code>static</code> <code>void</code> <code>main(String args[]) </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>{ </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>String bin = Integer.toBinaryString(</code><code>123</code><code>); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>String oct = Integer.toOctalString(</code><code>123</code><code>); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>String hex = Integer.toHexString(</code><code>123</code><code>); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>System.out.print(bin + </code><code>"\n"</code> <code>+ oct + </code><code>"\n"</code> <code>+ hex); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>} </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>} </code></span> 
         </div> 
        </div> </td> 
      </tr> 
     </tbody> 
    </table>
    
    **输出：**
    
        1111011
        173
        7b
3.  **对数据执行操作：** Integer类还允许我们反转数字或分别使用reverse（），rotateLeft（）和rotateRight（）左右旋转数字。我们需要定义自己的逻辑来对int变量执行这些操作，因为它不是内置类。
    
    *filter\_none*
    
    *编辑*
    
    *play\_arrow*
    
    *亮度\_4*
    
    <table style="width:607.844px;"> 
     <tbody> 
      <tr> 
       <td style="text-align:left;vertical-align:baseline;width:538px;"> 
        <div style="margin-left:0px;"> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>// Java program to illustrate&nbsp; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>// difference between </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>// int and Integer&nbsp; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;</code>&nbsp;</span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>public</code> <code>class</code> <code>Main { </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>public</code> <code>static</code> <code>void</code> <code>main(String args[]) </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>{ </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// mainethods convert integer to its binary form, </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// apply the desired operation&nbsp; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// and then returns the decimal form </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// of the newly formed binary number </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// (12)10-&gt;(1100)2 -&gt;&nbsp; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// rotate left by 2 units -&gt; (110000)2-&gt;(48)10 </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>int</code> <code>rL = Integer.rotateLeft(</code><code>12</code><code>, </code><code>2</code><code>); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;</code>&nbsp;</span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// (12)10-&gt;(1100)2 -&gt;&nbsp; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// rotate right by 2 units -&gt; (0011)2-&gt;(3)10 </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>int</code> <code>rR = Integer.rotateRight(</code><code>12</code><code>, </code><code>2</code><code>); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;</code>&nbsp;</span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>//(12)10 -&gt; (00000000000000000000000000001100)2&nbsp; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// -&gt; reverse -&gt;(00110000000000000000000000000000)2 </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// -&gt; (805306368)10 </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code>&nbsp;</span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>// int is of 32 bits </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>int</code> <code>rev = Integer.reverse(</code><code>12</code><code>); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>System.out.print(</code><code>"Left Rotate : "</code> <code>+ rL&nbsp; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>+ </code><code>"\nRight rotate : "</code> <code>+ rR + </code><code>"\nReverse : "</code> <code>+ rev); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>} </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>} </code></span> 
         </div> 
        </div> </td> 
      </tr> 
     </tbody> 
    </table>
    
    **输出：**
    
        左旋：48
        右旋转：3
        反向：805306368
4.  **灵活性：**整数包装器类为我们提供了对现有int数据类型的更大灵活性。除了预定义的运算符，我们还可以对int值执行许多操作。在需要将int变量像对象一样对待的地方使用Integer类。由于Wrapper类继承了Object类，因此可以在具有Object引用或泛型的集合中使用它们。因此，我们将可空性的属性添加到现有的int数据类型中。  
    从Java 5开始，我们有了[自动装箱][Link 2]的概念，其中原始数据类型自动转换为包装器类，反之亦然。因此，我们可以在任何原始数据类型和任何Wrapper类之间执行任何算术或逻辑运算。
    
    *filter\_none*
    
    *编辑*
    
    *play\_arrow*
    
    *亮度\_4*
    
    <table style="width:607.844px;"> 
     <tbody> 
      <tr> 
       <td style="text-align:left;vertical-align:baseline;width:488px;"> 
        <div style="margin-left:0px;"> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>// Java program to illustrate </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>// auto-boxing </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>import</code> <code>java.util.function.Function; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>import</code> <code>java.util.function.Function; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>public</code> <code>class</code> <code>Main { </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>public</code> <code>static</code> <code>void</code> <code>main(String args[]) </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>{ </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;</code>&nbsp;</span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>Integer a = </code><code>new</code> <code>Integer(</code><code>"12"</code><code>); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>Integer d = </code><code>new</code> <code>Integer(</code><code>"13"</code><code>); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>int</code> <code>b = </code><code>2</code><code>; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>double</code> <code>c = </code><code>3.1</code><code>; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>Double f = </code><code>new</code> <code>Double(</code><code>"12.1"</code><code>); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>int</code> <code>d2 = a + d; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>System.out.println(</code><code>"Sum of 2 Integer objects :"</code>&nbsp;</span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>+ (a + d)); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>System.out.println("Sum of an Integer object&nbsp; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>and </code><code>int</code> <code>value :" + (a + b)); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>System.out.println("Sum of an Integer object&nbsp; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>and </code><code>double</code> <code>value :" + (a + c)); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>System.out.println("Sum of an Integer object&nbsp; </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>and Double object :" + (a + f)); </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>} </code></span> 
         </div> 
         <div style="margin-left:0px;"> 
          <span style="color:#40424e;"><code>} </code></span> 
         </div> 
        </div> </td> 
      </tr> 
     </tbody> 
    </table>
    
    **输出：**
    
        2个整数对象的总和：25
        一个整数对象和int值的总和：14
        整数对象和double值的总和：15.1
        整数对象和双精度对象的总和：24.1

除了Integer，我们在Java中还有更多与数据类型相对应的[包装器类][Link 1]。给出如下：

**Java中基本类型的等效包装器类**

![f4aa295dc35798b192b72bee68403c79.png][]

[Link 1]: https://www.geeksforgeeks.org/wrapper-classes-java/
[Link 2]: https://www.geeksforgeeks.org/autoboxing-unboxing-java/
[f4aa295dc35798b192b72bee68403c79.png]: https://img-blog.csdnimg.cn/img_convert/f4aa295dc35798b192b72bee68403c79.png