Getting Document from workflow - custom step

I have a Java project using a Maven archetype provided by Adobe to get started.

I have built several custom workflow steps using this model - all is good.

Until now, all of them have been using typical data types such as Int, String, etc.

Now, I have a need to write a Document to the Filesystem.  Because I do not see an existing component to do this, I will need to build my own custom step.

I expect the code will be something like this:

com.adobe.aemfd.docmanager.Document doc = wfd.getMetaDataMap().get("myDoc");

However the package com.adobe.aemfd.docmanager isn't in the project setup.  I'm a novice at Maven and adding libraries so, any help to bootstrap this quickly would be helpful.

Thanks,