It's probably a stupid question, but I can't figure out how to properly import a folder of
You should not use the sources directly. You should start to use maven (or gradle). In that case you can simply add a dependency:
<dependency> <groupId>javax.money</groupId> <artifactId>money-api</artifactId> <version>1.0.1</version> </dependency>
If you don't want to use maven, you should import the existing maven project from the repository and export it as a *.jar file.
Or you simply download the prebuilt version from a mvn-repository.