Series of roles that fields can be performing in the (ORM) mapping process.
This is typically for use by mapped datastores, but relates to MetaData definitions too, so is
stored in org.datanucleus.metadata.
Returns the enum constant of this type with the specified name.
The string must match exactly an identifier used to declare an
enum constant in this type. (Extraneous whitespace characters are
not permitted.)
Parameters:
name - the name of the enum constant to be returned.