This class provides utilities for analyzing patterns in relation with the
ECFieldSpec specification class.
Patterns may be in one of the following forms :
epc-tag type :
urn:epc:pat:sgtin-96:FilterValue.CompanyPrefix.ItemReference.SerialNumber
urn:epc:pat:sgln-96:FilterValue.CompanyPrefix.LocationReference.ExtensionComponent
epc-pure type :
urn:epc:idpat:sgtin:CompanyPrefix.ItemReference.SerialNumber
urn:epc:idpat:sgln:CompanyPrefix.LocationReference.ExtensionComponent
(Optional) An ordered list that specifies a set of fields which together constitute
the "primary key" for determining Tag uniqueness, as described below.