I inherited a Schema Definition that I must validate against. However, the schema cannot be parsed as it is violating "Unique Particle Attribution". (I'll put the details below.) Unfortunately, I have little experience writing schemas and despite several hours with Google and a few XML/XSD books at my side, I have not been able to find a way to accomplish what the schema is attempting to accomplish. So I am asking my fellow ranchers for a hand.
Basically, the intent is the schema wants to enforce that a <foo> element always has either a <prefoo>, a <postfoo>, or both; so a <foo> element cannot exist alone. The <foo> element is (ultimately) a child of a <dataInformation> element.
Here is an excerpt from the schema:
When I attempt to parse the schema to use in validation, the following exception occurs:
org.xml.sax.SAXParseException: cos-nonambig: "":prefoo and "":prefoo (or elements from their substitution group) violate "Unique Particle Attribution". During validation against this schema, ambiguity would be created for those two particles.
Any suggestions on how I can rework the schema to get the desired affect of ensuring a <foo> element is always accompanied by a <prefoo>, OR a <postfoo> OR both?