在 Java 中实现重试逻辑

深碍√TFBOYSˉ_ 2023-09-26 23:52 22阅读 0赞

这篇文章将讨论如何在 Java 中实现重试逻辑。

### 1. 简单的 for 循环与 try-catch ###

在 Java 中实现重试逻辑的一个简单解决方案是将代码编写在执行指定次数（最大重试值）的 for 循环中。

以下程序对此进行了演示。请注意，代码包含在 try-catch 中，如果 try 块内发生异常，控件将转到 catch 块。处理异常后，系统会在 1 秒后再次运行代码。在所有重试都用尽并且最后一次重试失败后，系统会引发异常。

[下载][Link 1][运行代码][Link 2]

**输出（会有所不同）：**  
随机数是.. 0 / 乘以零 随机数为.. 0  
  
/ 乘以零  
  
随机数为.. 1

### 2. 使用界面 ###

我们可以轻松地调整上述逻辑，以使用接口将任务逻辑与重试逻辑隔离开来。以下代码对此进行了演示。

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    </div> </td> 
   <td style="text-align:left;vertical-align:top;"> 
    <div style="margin-left:0;text-align:left;"> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;"><span style="color:#800080;">import</span> <span style="color:#002d7a;">java</span><span style="color:#333333;">.</span><span style="color:#002d7a;">util</span><span style="color:#333333;">.</span><span style="color:#002d7a;">Random</span><span style="color:#333333;">;</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;</span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;"><span style="color:#800080;">interface</span> <span style="color:#004ed0;">Task</span> <span style="color:#333333;">{ </span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#800080;">void</span> <span style="color:#004ed0;">run</span><span style="color:#333333;">(</span><span style="color:#333333;">)</span><span style="color:#333333;">;</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#800080;">void</span> <span style="color:#004ed0;">handleException</span><span style="color:#333333;">(</span><span style="color:#004ed0;">Exception </span><span style="color:#002d7a;">ex</span><span style="color:#333333;">)</span><span style="color:#333333;">;</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;"><span style="color:#333333;">}</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;</span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;"><span style="color:#800080;">public</span> <span style="color:#800080;">class</span> <span style="color:#004ed0;">Main</span> <span style="color:#333333;">{ </span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#800080;">private</span> <span style="color:#800080;">static</span> <span style="color:#800080;">final</span> <span style="color:#800080;">int</span> <span style="color:#002d7a;">MAX_RETRIES</span> <span style="color:#006fe0;">=</span> <span style="color:#ce0000;">5</span><span style="color:#333333;">;</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;</span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#800080;">public</span> <span style="color:#800080;">static</span> <span style="color:#800080;">void</span> <span style="color:#004ed0;">withMaxRetries</span><span style="color:#333333;">(</span><span style="color:#004ed0;">Task </span><span style="color:#002d7a;">task</span><span style="color:#333333;">)</span> <span style="color:#333333;">{ </span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#800080;">for</span> <span style="color:#333333;">(</span><span style="color:#800080;">int</span> <span style="color:#002d7a;">i</span> <span style="color:#006fe0;">=</span> <span style="color:#ce0000;">0</span><span style="color:#333333;">;</span> <span style="color:#002d7a;">i</span> <span style="color:#006fe0;">&lt;=</span> <span style="color:#002d7a;">MAX_RETRIES</span><span style="color:#333333;">;</span> <span style="color:#002d7a;">i</span><span style="color:#006fe0;">++</span><span style="color:#333333;">)</span> <span style="color:#333333;">{ </span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#800080;">try</span> <span style="color:#333333;">{ </span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#002d7a;">task</span><span style="color:#333333;">.</span><span style="color:#004ed0;">run</span><span style="color:#333333;">(</span><span style="color:#333333;">)</span><span style="color:#333333;">;</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#800080;">break</span><span style="color:#333333;">;</span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#008200;">// don't retry on success</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#333333;">}</span> <span style="color:#800080;">catch</span> <span style="color:#333333;">(</span><span style="color:#004ed0;">Exception </span><span style="color:#002d7a;">ex</span><span style="color:#333333;">)</span> <span style="color:#333333;">{ </span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#002d7a;">task</span><span style="color:#333333;">.</span><span style="color:#004ed0;">handleException</span><span style="color:#333333;">(</span><span style="color:#002d7a;">ex</span><span style="color:#333333;">)</span><span style="color:#333333;">;</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;</span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#008200;">// throw exception if the last re-try fails</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#800080;">if</span> <span style="color:#333333;">(</span><span style="color:#002d7a;">i</span> <span style="color:#006fe0;">==</span> <span style="color:#002d7a;">MAX_RETRIES</span><span style="color:#333333;">)</span> <span style="color:#333333;">{ </span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#800080;">throw</span> <span style="color:#002d7a;">ex</span><span style="color:#333333;">;</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#333333;">}</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#333333;">}</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#333333;">}</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#333333;">}</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;</span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#800080;">public</span> <span style="color:#800080;">static</span> <span style="color:#800080;">void</span> <span style="color:#004ed0;">main</span><span style="color:#333333;">(</span><span style="color:#800080;">String</span><span style="color:#333333;">[</span><span style="color:#333333;">]</span> <span style="color:#002d7a;">args</span><span style="color:#333333;">)</span> <span style="color:#333333;">{ </span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#004ed0;">withMaxRetries</span><span style="color:#333333;">(</span><span style="color:#800080;">new</span> <span style="color:#004ed0;">Task</span><span style="color:#333333;">(</span><span style="color:#333333;">)</span> <span style="color:#333333;">{ </span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#666666;">@Override</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#800080;">public</span> <span style="color:#800080;">void</span> <span style="color:#004ed0;">run</span><span style="color:#333333;">(</span><span style="color:#333333;">)</span> <span style="color:#333333;">{ </span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#008200;">// generate 0 or 1 with equal probability</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#800080;">int</span> <span style="color:#002d7a;">zeroOrOne</span> <span style="color:#006fe0;">=</span> <span style="color:#800080;">new</span> <span style="color:#004ed0;">Random</span><span style="color:#333333;">(</span><span style="color:#333333;">)</span><span style="color:#333333;">.</span><span style="color:#004ed0;">nextInt</span><span style="color:#333333;">(</span><span style="color:#ce0000;">2</span><span style="color:#333333;">)</span><span style="color:#333333;">;</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;</span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#002d7a;">System</span><span style="color:#333333;">.</span><span style="color:#002d7a;">out</span><span style="color:#333333;">.</span><span style="color:#004ed0;">println</span><span style="color:#333333;">(</span><span style="color:#880000;">"Random number is.. "</span> <span style="color:#006fe0;">+</span> <span style="color:#002d7a;">zeroOrOne</span><span style="color:#333333;">)</span><span style="color:#333333;">;</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;</span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#008200;">// 50% probability of getting java.lang.ArithmeticException: / by zero</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#800080;">int</span> <span style="color:#002d7a;">rand</span> <span style="color:#006fe0;">=</span> <span style="color:#ce0000;">1</span> <span style="color:#006fe0;">/</span> <span style="color:#002d7a;">zeroOrOne</span><span style="color:#333333;">;</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#333333;">}</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;</span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#666666;">@Override</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#800080;">public</span> <span style="color:#800080;">void</span> <span style="color:#004ed0;">handleException</span><span style="color:#333333;">(</span><span style="color:#004ed0;">Exception </span><span style="color:#002d7a;">ex</span><span style="color:#333333;">)</span> <span style="color:#333333;">{ </span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#002d7a;">System</span><span style="color:#333333;">.</span><span style="color:#002d7a;">out</span><span style="color:#333333;">.</span><span style="color:#004ed0;">println</span><span style="color:#333333;">(</span><span style="color:#002d7a;">ex</span><span style="color:#333333;">.</span><span style="color:#004ed0;">getMessage</span><span style="color:#333333;">(</span><span style="color:#333333;">)</span><span style="color:#333333;">)</span><span style="color:#333333;">;</span>&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#008200;">// log the exception</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;</span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#800080;">try</span> <span style="color:#333333;">{ </span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#008200;">// sleep for 1 seconds before retrying (Optional)</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#002d7a;">Thread</span><span style="color:#333333;">.</span><span style="color:#004ed0;">sleep</span><span style="color:#333333;">(</span><span style="color:#ce0000;">1000</span><span style="color:#333333;">)</span><span style="color:#333333;">;</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#333333;">}</span> <span style="color:#800080;">catch</span> <span style="color:#333333;">(</span><span style="color:#000000;">InterruptedException</span> <span style="color:#002d7a;">e</span><span style="color:#333333;">)</span> <span style="color:#333333;">{ </span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#002d7a;">System</span><span style="color:#333333;">.</span><span style="color:#002d7a;">out</span><span style="color:#333333;">.</span><span style="color:#004ed0;">println</span><span style="color:#333333;">(</span><span style="color:#002d7a;">e</span><span style="color:#333333;">.</span><span style="color:#004ed0;">getMessage</span><span style="color:#333333;">(</span><span style="color:#333333;">)</span><span style="color:#333333;">)</span><span style="color:#333333;">;</span>&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#008200;">// log the exception</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#333333;">}</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#333333;">}</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#333333;">}</span><span style="color:#333333;">)</span><span style="color:#333333;">;</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;">&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#333333;">}</span></span></span> 
     </div> 
     <div style="margin-left:0;text-align:left;"> 
      <span style="color:#61738e;"><span style="color:#000000;"><span style="color:#333333;">}</span></span></span> 
     </div> 
    </div> </td> 
  </tr> 
 </tbody> 
</table>

[下载][Link 3][运行代码][Link 4]

**输出（会有所不同）：**  
随机数是.. 0 / 乘以零 随机数为.. 0 / 乘以零 随机数为.. 0  
  
/ 乘以零  
  
  
随机数为.. 1

### 3. 第三方库 ###

如果您的项目准备使用第三方库，我们建议您使用以下库，这些库在 Java 中对重试逻辑有很强的支持。

#### 1. 故障安全 ####

故障保护是一个轻量级的零依赖库，用于处理 Java 8+ 中的故障。故障保护的工作原理是将可执行逻辑与一个或多个弹性策略包装在一起，这些策略可以根据需要组合和组合。

首先，创建一个重试策略，该策略定义应处理哪些故障以及何时应执行重试：

然后，您可以重试执行 或：`Runnable``Supplier`

阅读更多 – [故障安全文档][Link 5]

#### 2. 番石榴重试 ####

guava 重试模块提供了一种通用方法，用于重试任意 Java 代码，具有特定的停止、重试和异常处理功能，这些功能通过 Guava 的谓词匹配得到增强。

某些功能的最小示例如下所示：

每当 的结果为 null、引发 或从方法中抛出任何其他结果时，这将重试。它将在尝试重试 3 次后停止，并抛出包含有关上次失败尝试的信息的 。如果从方法中弹出任何其他内容，则会将其包装并重新抛出。`Callable``IOException``RuntimeException``call()``RetryException``Exception``call()``ExecutionException`

阅读更多 – [番石榴重试文档][Link 6]

这就是在 Java 中实现重试逻辑的全部内容。

[Link 1]: https://www.techiedelight.com/code/Sn7Asu
[Link 2]: https://techiedelight.com/compiler/?run=Sn7Asu
[Link 3]: https://www.techiedelight.com/code/NXIUBf
[Link 4]: https://techiedelight.com/compiler/?run=NXIUBf
[Link 5]: https://failsafe.dev/
[Link 6]: https://github.com/rholder/guava-retrying