backend/doc/rule.md

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# 阿里巴巴java规范checkstyle

我们使用阿里巴巴java规范泰山版（1.6.0）

需使用idea(版本2018.3+)安装插件，自动检查代码规范，具体操作步骤如下：

## 本地安装Alibaba Java Coding Guidelines

1、安装

- Mac：IntelliJ IDEA -> Preferences -> Plugins -> Installed plugins from Disk -> 选择doc目录下的code-guidelines进行安装
- Windows：File -> Settings -> Plugins -> Installed plugins from Disk -> 选择doc目录下的code-guidelines进行安装

2、重启idea

## 在线安装Alibaba Java Coding Guidelines

1、安装

- Mac：IntelliJ IDEA -> Preferences -> Plugins -> Browse repositories -> 搜索Alibaba Java Coding Guidelines -> 直接install进行在线安装
- Windows：File -> Settings -> Plugins -> Marketplace -> 搜索Alibaba Java Coding Guidelines -> 直接install进行在线安装

2、重启idea

# spotless插件规范代码

另外，我们还使用了spotless这款插件来规范代码。在backend/pom.xml中添加spotless插件：

```
<plugin>
  <groupId>com.diffplug.spotless</groupId>
  <artifactId>spotless-maven-plugin</artifactId>
  <version>${spotless.version}</version>
  <configuration>
    <java>
      <googleJavaFormat>
        <version>1.7</version>
        <style>GOOGLE</style>
      </googleJavaFormat>
      <importOrder>
        <order>org.apache.iotdb,,javax,java,\#</order>
      </importOrder>
      <removeUnusedImports/>
    </java>
    <lineEndings>UNIX</lineEndings>
  </configuration>
  <executions>
    <execution>
      <id>spotless-check</id>
      <phase>validate</phase>
      <goals>
        <goal>check</goal>
      </goals>
    </execution>
  </executions>
</plugin>
```

添加成功后我们可以看见在Maven出现了spotless插件，点击check可检查代码是否满足规范，点击apply可自动格式化代码使其满足规范。此外，在Maven打包时会自动check，如果没通过，打包就不会成功。

![](image/spotless.png)