Structure:
tempalates/seatBooking.html:
<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="UTF-8">
<title>com.virtualpairprogrammers.theater.services.TheaterService Booking</title>
</head>
<body>
<h1>com.virtualpairprogrammers.theater.services.TheaterService Booking</h1>
<h2>Seat availability</h2>
<form action="/checkAvailability" th:object="${bean}" method="POST">
<p>Check if seat number
<select th:field="*{selectedSeatNum}">
<option th:each="n : ${bean.seatNums}" th:value="${n}" th:text="${n}" />
</select>
in row
<select th:field="*{selectedSeatRow}">
<option th:each="r : ${bean.seatRows}" th:value="${r}" th:text="${r}" />
</select>
is available <input type="submit"/></p>
</form>
<p th:text="${bean.result}"></p>
</body>
</html>
Control/MainController:
package com.virtualpairprogrammers.theater.control
import com.virtualpairprogrammers.theater.services.BookingService
import com.virtualpairprogrammers.theater.services.TheaterService
import org.springframework.beans.factory.annotation.Autowired
import org.springframework.stereotype.Controller
import org.springframework.web.bind.annotation.RequestMapping
import org.springframework.web.bind.annotation.RequestMethod
import org.springframework.web.servlet.ModelAndView
@Controller
class MainController {
@Autowired
lateinit var theaterService: TheaterService
@Autowired
lateinit var bookingService: BookingService
@RequestMapping("")
fun homePage() : ModelAndView {
return ModelAndView("seatBooking", "bean", CheckAvailabilityBackingBean())
}
@RequestMapping("checkAvailability", method= arrayOf(RequestMethod.POST))
fun checkAvailability(bean: CheckAvailabilityBackingBean): ModelAndView {
val selectedSeat = theaterService.find(bean.selectedSeatNum, bean.selectedSeatRow)
val result = bookingService.isSeatFree(selectedSeat)
bean.result = "Seat $selectedSeat is " + if (result) "available" else "booked"
return ModelAndView("seatBooking", "bean", bean)
}
}
/*
* A typical JavaServer Faces application includes one or more backing beans,
* each of which is a type of JavaServer Faces managed bean that can be associated with
* the components used in a particular page.
* This section introduces the basic concepts of creating, configuring,
* and using backing beans in an application.
* */
class CheckAvailabilityBackingBean() {
val seatNums = 1..36
val seatRows = 'A'..'O'
// below must be var because those data are sent back and forward between
// server and template
var selectedSeatNum: Int = 1
var selectedSeatRow: Char = 'A'
var result: String = ""
}
domain/Seat:
package com.virtualpairprogrammers.theater.domain
import java.math.BigDecimal
data class Seat(val row: Char, val num: Int, val price: BigDecimal, val description: String) {
override fun toString(): String = "Seat $row-$num $$price ($description)"
}
services/TheaterService:
package com.virtualpairprogrammers.theater.services
import com.virtualpairprogrammers.theater.domain.Seat
import org.springframework.stereotype.Service
import java.math.BigDecimal
@Service
class TheaterService {
private val hiddenSeats = mutableListOf<Seat>()
constructor() {
fun getPrice(row: Int, num: Int) : BigDecimal {
return when {
row >=14 -> BigDecimal(14.50)
num <=3 || num >= 34 -> BigDecimal(16.50)
row == 1 -> BigDecimal(21)
else -> BigDecimal(18)
}
}
fun getDescription(row: Int, num: Int) : String {
return when {
row == 15 -> "Back Row"
row == 14 -> "Cheaper Seat"
num <=3 || num >= 34 -> "Restricted View"
row <=2 -> "Best View"
else -> "Standard Seat"
}
}
for (row in 1..15) {
for (num in 1..36) {
hiddenSeats.add(Seat((row+64).toChar(), num, getPrice(row,num), getDescription(row,num) ))
}
}
}
val seats
get() = hiddenSeats.toList()
fun find(num: Int, row: Char): Seat {
return seats.filter {it.row === row && it.num === num }.first()
}
}
services/BookingService:
package com.virtualpairprogrammers.theater.services
import com.virtualpairprogrammers.theater.domain.Seat
import org.springframework.stereotype.Service
@Service
class BookingService() {
fun isSeatFree(seat: Seat): Boolean {
return true
}
}