BIO和NIO的精髓

系统管理员 2022-12-27 01:19 129阅读 0赞

# 什么是I/O #

![在这里插入图片描述][20201206201315665.png]

![20201206201211580.png][]  
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## 同步阻塞I/O非阻塞I/O ##

![在这里插入图片描述][20201206202515400.png]

### 同步阻塞I/O ###

#### 文件读写I/O ####

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#### 网络读写I/O示例 ####

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先启动java应用程序  
![在这里插入图片描述][20201206203657990.png]

![在这里插入图片描述][20201206203741640.png]  
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可以使用多线程来解决阻塞问题，每来一个连接放入一个线程中  
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### 同步非阻塞I/O ###

文件I/O  
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## IO复用 ##

IO复用主要用于网络I/O, 多个客户端来了之后在服务端注册登记，一个线程就可以处理多个客户端的连接请求。  
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## 异步I/O ##

异步I/O没有阻塞的概念  
![在这里插入图片描述][20201206210026266.png]  
![在这里插入图片描述][20201206213723674.png]  
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Netty的底层也是通过NIO实现的  
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# 面试题： #

![在这里插入图片描述][20201206213331779.png]

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