This is a Java API that lets you programmatically create an EML document and write it out to an XML file. This file could then be loaded into DataONE amongst other things.

This project is maintained by TERN Eco-informatics (http://ecoinformatics.org.au/) who are based in Australia. 
This is not the same organisation as the Eco-informatics team that provide other products (such as Morpho) that work with EML.