How do I manage a graph schema in JanusGraph?

Question

I'm struggling with how to set up the schema for a graph. I'm using ConfigureGraphFactory and I'm able to define the schema through the Gremlin console and a Groovy startup script. The Gremlin script isn't sustainable when I'm working on a deployment at any stage, test through prod, and the Groovy startup script isn't a good solution when I'm developing and experimenting.

I created a Java class that initializes a graph, but I can't get it to work because I'm unable to get a JanusGraphManagement object. The question I originally planned to ask was essentially this.

Is there a way to manage schemas that doesn't require me to either restart the database or manually run each line?