Maven Spring JUnit 在Maven Clean Install时报

问题: Maven Clean Install时, 遇到报错package org.junit does not exist

明显, Unit Test在Compile阶段就被检查了.

而POM.xml里面配置的是:

<dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.12</version>
    <scope>test</scope>
</dependency>

所以导致问题发生.

但是为何在Compile阶段(而非Test Phase)就开始读Unit Test代码呢?

原因在于我错误的人为设置了Project的sourceDirectory, 

<build>
    <finalName>demo</finalName>
    <sourceDirectory>src</sourceDirectory>
    <plugins>
        <plugin>
        ...
        </plugin>
    </plugins>
</build>

参考自:

http://stackoverflow.com/questions/28173431/maven-error-package-org-junit-does-not-exist