How to deal with missing src/test/java source folder in Android/Maven project?

I realise this annoying thing too since latest m2e-android plugin upgrade (version 0.4.2), it happens in both new project creation and existing project import (if you don’t use src/test/java).

It looks like m2e-android (or perhaps m2e) now always trying to add src/test/java as a source folder, regardless of whether it is actually existed in your project directory, in the .classpath file:

<classpathentry kind="src" output="bin/classes" path="src/test/java">
  <attributes>
    <attribute name="maven.pomderived" value="true"/>
  </attributes>
</classpathentry>

As it is already added in the project metadata file, so if you trying to add the source folder via Eclipse, Eclipse will complain that the classpathentry is already exist:

There are several ways to fix it, the easiest is manually create src/test/java directory in the file system, then refresh your project by press F5 and run Maven -> Update Project (Right click project, choose Maven -> Update Project…), this should fix the missing required source folder: ‘src/test/java’ error.