DOMJson permit to represent a json stream how document objects.
To the contrary of SAJ the json representation is all in memory and can be navigate and modified.
DOMJson supply an abstract API where is possible use different implementation without obligate the developer to one implementation.
Any implementation can be used and configured using the FactoryFinder project (see FactoryFinder javadoc)
DOMJson default implementation use SAJ and it uses the SAJ schema support (please see SAJ).
Other implementation could be use another methodology but all MUST use the SAJ interfaces of Schemas to supply the validation.
DOMJson supply the JSONPath support to navigate in json DOM using the search path.
These release support principal features of JSONPath specification with some limitation (see documentation).