August 2020
Intermediate to advanced
483 pages
11h 24m
Chinese
Content preview from Head First Kotlin程序设计
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410 附录
ii
JUnit
正如你所知，
Kotlin
的代码可以被编译成
Java
、
JavaScript
或者本
地代码，因此你可以使用目标平台的现有库。就测试而言，这意
味着你可以用
Java
和
JavaScript
中最受欢迎的测试库去测试
Kotlin
的代码。
让我们看看如何用
JUnit
对
Kotlin
代码进行单元测试。
Kotlin
可以使用现有的测试库
添加
JUnit
库
JUnit
库（https://junit.org）是使用频率最高的
Java
测试库。
要想在
Kotlin
项目中使用
JUnit
，首先需要将
Junit
库添加到你的项
目中。你可以进入
File
菜单依次选择
Project Structure
→
Libraries
去添加库；如果是
Gradle
项目，添加下面这些代码行到你的
build.gradle文件：
dependencies {
....
testImplementation 'org.junit.jupiter:junit-jupiter-api:5.3.1'
testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.3.1'
test { useJUnitPlatform() }
....
}
一旦代码编译后，你就可以右键类或者函数名然后选择Run选项去
执行测试。
为了了解如何在
Kotlin
中使用
JUnit
，我们将为下面的Totaller类
编写一个测试：该类使用一个Int值初始化，并且该类保存当前
add函数所加的总和。
class Totaller(var ...
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.