*******************************************************************************************************************

view
	enquiry.jsp		--		flight enquiry form
	result.jsp		--		show the query result
	travelCorner.jsp	--		show the travel plan corner and state of insertion and deletion

Controller
	controller.java		--		implement the doPost doGet method execute service class to process
						and forward result to specific view 

Service
	Service.java		--		An interface that provides the base functionality for all Services
	database.java		--		initialize, query the database
	travelCorner.java	--		Travel plan corner
	CornerService.java	--		add the flight information to the travel plan corner
						remove the flight information from the travel plan corner
	checkOut.java		--		end the session

********************************************************************************************************************

