After reading and investigating a few documents, I have tried implementing the ARQ API to query the imported triple store. The implementation is put in my TripleStoreHandler class which manage the input and the output of rdf graphs.
The current status is the application can make simple call to the store referred in the designated "ttl" file with a query string. The call will return a list with mappings that include all the binding variables issued in the query. The types of SPARQL query can vary in "select","describe","construct","ask". I tried to streamline the result set which is returned from the query so that the application does not have to look inside the query string itself.
Right now the "select" type query is tested. I am testing more for "describe" and "ask" types of query. "Construct" type should be integrated, too. However I think the usage of "construct" query would be less.