Best practices for importing multiple xml files

Newbie here. I need to import multiple xml files into Neo4j. Each file represents an entity, let's call it a Thing. The outer element is Things, so each file looks approximately like

<Things>
  <Thing ....>
    ...
  </Thing>
</Things>

I can import one in the Neo4J browser using apoc.import.xml and get a reasonable looking graph.

Just not sure how to add a second (and subsequent) xml to the graph, nor how to do it in scala/java, which is where we want to get to.

Any help appreciated.