> For the complete documentation index, see [llms.txt](https://ethan-lin.gitbook.io/refactoring/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ethan-lin.gitbook.io/refactoring/dan-wei-zhuan-huan/1-project-description.md).

# 题目介绍

现在，我们先用一道题目来开始热身。这是一道简单的长度单位之间的换算题，代码已经由你的前任程序员写好，但是……实现实在并不怎么优雅，好在前任还算负责，写了很多单元测试。这一课的任务就是对已有的代码做出修改，使它变得更可读，维护性更好。你可以先把代码拉下来，读读`README.md`里描述的需求，再随意读读代码感受一下，有兴趣的话你也可以尝试上手重构一把。

Java：

```
git clone https://github.com/linesh-simplicity/length-java.git
cd length-java
./gradlew clean build
```

JavaScript：

```
git clone https://github.com/linesh-simplicity/length.git
cd length
npm test
```


---

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