the following files carry various aspects for the generated pom:
*.gemspec is used to setup dependencies and metadata (name, description, authors, etc)
Gemfile,Gemfile.lock declare the gem dependencies
Jarfile, Jarfile.lock declare the jar/pom dependencies (a pom here is jar dependencies without jar but other dependencies)
Mavenfile has all the remaining maven related configurtions like resources, profiles, plugins, etc
the pom generation obeys all these files and adds some "reasonable" defaults to them. i.e. if there is rspec gem and there is a spec directory then a rspec plugin gets configured to execute rspec during thetest-phase. such a configuration can be overwritten inside Mavenfile.