面试题：redis是单线程、StringBuffer是线程安全的

墨蓝 2023-10-12 18:08 70阅读 0赞

## 1、说明String 和StringBuffer的区别 ##

<table style="width:500px;"> 
 <tbody> 
  <tr> 
   <td>类</td> 
   <td>底层/ 可变？</td> 
   <td>线程安全</td> 
  </tr> 
  <tr> 
   <td>String</td> 
   <td>final char[] 不可变</td> 
   <td>是</td> 
  </tr> 
  <tr> 
   <td>StringBuffer</td> 
   <td>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;char[] 可变&nbsp;</td> 
   <td>是（synchronized方法）</td> 
  </tr> 
  <tr> 
   <td>StringBuilder</td> 
   <td>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;char[] 可变</td> 
   <td>否</td> 
  </tr> 
 </tbody> 
</table>

[(4条消息) Java基础：String、StringBuffer、StringBuilder的区别\_string stringbuffer stringbuilder区别\_heiqi\_whf的博客-CSDN博客][4_ Java_String_StringBuffer_StringBuilder_string stringbuffer stringbuilder_heiqi_whf_-CSDN]

## 2、Redis是单线程还是多线程？ ##

![d9c94a0914da4905bfbfff86b902e8c1.png][]

Redis单线程为啥还这么快？

![fa878f1566ae4e728a26deb177dde721.png][]

![62b8b87489b44399b2a1da6bc96199c2.png][]

![0223af7f5b5b422696bc163318940b45.png][]

Java特性：![27d90fc7c1504857b612e78fb59f37fa.png][]

高并发中的集合有哪些问题？![4e8050cde4154ab29fc6bc541dae8a28.png][]

![ce6e52324d0643ed89ef6d9052ddc661.png][]

[4_ Java_String_StringBuffer_StringBuilder_string stringbuffer stringbuilder_heiqi_whf_-CSDN]: https://blog.csdn.net/weixin_42188778/article/details/124527355?ops_request_misc=&request_id=&biz_id=102&utm_term=stringbuffer%E5%92%8Cstringbuilder&utm_medium=distribute.pc_search_result.none-task-blog-2~all~sobaiduweb~default-2-124527355.nonecase&spm=1018.2226.3001.4187
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[62b8b87489b44399b2a1da6bc96199c2.png]: https://img-blog.csdnimg.cn/62b8b87489b44399b2a1da6bc96199c2.png
[0223af7f5b5b422696bc163318940b45.png]: https://img-blog.csdnimg.cn/0223af7f5b5b422696bc163318940b45.png
[27d90fc7c1504857b612e78fb59f37fa.png]: https://img-blog.csdnimg.cn/27d90fc7c1504857b612e78fb59f37fa.png
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