Вместо Value (Long) значение Null передается в JSP, поэтому правильные значения не отображаются на JSP страницах.

Question

У меня есть объект резервирования как:

package com.nischal.flightreservation.entities;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.OneToOne;
import javax.persistence.Table;


@Entity
@Table(name = "RESERVATION")
public class Reservation extends AbstractEntity{
@Column(name = "checked_in")
private Boolean checkedIn;
@Column(name = "no_of_bags")
private int noOfBags;
@OneToOne
private Passenger passenger;
@OneToOne
private Flight flight;

public Boolean getCheckedIn() {
    return checkedIn;
}

public void setCheckedIn(Boolean checkedIn) {
    this.checkedIn = checkedIn;
}

public int getNoOfBags() {
    return noOfBags;
}

public void setNoOfBags(int noOfBags) {
    this.noOfBags = noOfBags;
}

public Passenger getPassenger() {
    return passenger;
}

public void setPassenger(Passenger passenger) {
    this.passenger = passenger;
}

public Flight getFlight() {
    return flight;
}

public void setFlight(Flight flight) {
    this.flight = flight;
}

@Override
public String toString() {
    return "Reservation [checkedIn=" + checkedIn + ", noOfBags=" + noOfBags + ", passenger="
            + passenger + ", flight=" + flight + "]";
}

}

У меня есть класс абстрактного объекта как:

package com.nischal.flightreservation.entities;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.MappedSuperclass;

@MappedSuperclass
public class AbstractEntity {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;

public Long getId() {
    return id;
}

public void setId(Long id) {
    this.id = id;
}

}

У меня FlightController есть:

package com.nischal.flightreservation.controllers;
import java.util.Date;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.format.annotation.DateTimeFormat;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import com.nischal.flightreservation.entities.Flight;
import com.nischal.flightreservation.repos.FlightRepository;

@Controller
public class FlightController {

@Autowired
private FlightRepository flightRepository;

@RequestMapping("/findFlights")
public String findFlights(@RequestParam(name = "from") String from, @RequestParam(name = "to") String to,@RequestParam(name = "departureDate") @DateTimeFormat(pattern = "dd-MM-yyyy") Date departureDate ,ModelMap modelMap) {
    List<Flight> flights = flightRepository.findFlights(from, to, departureDate);
    modelMap.addAttribute("flights",flights);

    return "displayFlights";

}

}

У меня есть «displayFlights. jsp», который отвечает за отображение всех доступных рейсов и работает нормально.

<table>
    <tr>
        <th>Airlines</th>
        <th>Departure City</th>
        <th>Arrival City</th>
        <th>Departure Time</th>
    </tr>
    <c:forEach items = "${flights}" var = "flight">
    <tr>
        <td>${ flight.operatingAirlines}</td>
        <td>${ flight.departureCity}</td>
        <td>${ flight.arrivalCity}</td>
        <td>${ flight.estimatedDepartureTime}</td>
        <td><a href = "showCompleteReservation?flightId=${flight.id }">Select</a>
    </tr>
    </c:forEach>

</table>

У меня ReservationController как:

package com.nischal.flightreservation.controllers;
import javax.validation.Valid;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import com.nischal.flightreservation.dto.ReservationRequest;
import com.nischal.flightreservation.entities.Flight;
import com.nischal.flightreservation.entities.Reservation;
import com.nischal.flightreservation.repos.FlightRepository;
import com.nischal.flightreservation.services.ReservationService;

@Controller
public class ReservationController {

@Autowired
FlightRepository flightRepository;

@Autowired
ReservationService reservationService;



@RequestMapping("/showCompleteReservation")
public String showCompleteReservation(@RequestParam("flightId") int flightId,ModelMap 
modelMap) {
    Flight flight = flightRepository.findById((long) flightId).orElse(null);
    modelMap.addAttribute("flight",flight);
    return "completeReservation";
}

@RequestMapping(value = "/completeReservation", method = RequestMethod.POST)
public String completeReservation(ReservationRequest request, 
        @Valid Reservation reservation, BindingResult bindingResult,ModelMap modelMap) {
    if(bindingResult.hasErrors()) {
        return "completeReservation";
    }
    else {
    modelMap.addAttribute("msg", "Reservation Saved Successfully. "+reservation.getId());
    return "reservationConfirmation";
    }
}

}

и completeReservation. jsp имеет вид:

<code><html>
<head>
<meta charset="UTF-8">
<title>Reservation Info</title>
</head>
<body>

Airline: ${flight.operatingAirlines }<br>
Departure City: ${flight.operatingAirlines }<br>
Arrival City: ${flight.arrivalCity }<br>

<form action = "completeReservation" method = "post">
    <pre>
        <h2>Passenger Details</h2>
        First Name: <input type = "text" name = "passengerFirstName"/>
        Middle Name: <input type = "text" name = "passengerMiddleName"/>
        Last Name: <input type = "text" name = "passengerLastName"/>
        Email: <input type = "email" name = "passengerEmail"/>
        Phone: <input type = "text" name = "passengerPhone"/>

        <h2>Card Details</h2>
        Name on the Card: <input type = "text" name = "nameOnTheCard"/>
        Card Number: <input type = "text" name = "cardNumber"/>
        Expiration Date: <input type = "text" name = "expirationDate"/>
        Three Digit Sec Code: <input type = "text" name = "threeDigitSecCode"/>
        <input type = "hidden" name = "flightId" value = "${flight.id }"/>
        <input type = "Submit" value = "Confirm"/>


    

Но вместо отображения названия действующих авиакомпаний, города вылета, города прибытия ничего не отображается. Я приложил фотографию здесь как:

и всякий раз, когда я нажимаю на кнопку подтверждения. Сообщение о резервировании отображается как:

Я хочу, чтобы идентификатор резервирования был там, а не ноль.