@Transaction Annotation use

 package com.javaTechie.flightserviceexample.service;

import java.util.UUID;

import javax.transaction.Transactional;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Service;

import com.javaTechie.flightserviceexample.dto.FlightBookingAcknowledgement;

import com.javaTechie.flightserviceexample.dto.FlightBookingRequest;

import com.javaTechie.flightserviceexample.entity.PassengerInfo;

import com.javaTechie.flightserviceexample.entity.PaymentInfo;

import com.javaTechie.flightserviceexample.repo.PassengerInfoRepository;

import com.javaTechie.flightserviceexample.repo.PaymentInfoRepository;

import com.javaTechie.flightserviceexample.utils.PaymentUtils;

@Service

public class FlightBookingService {

@Autowired

private PassengerInfoRepository passengerInfoRepository;

@Autowired

private PaymentInfoRepository paymentInfoRepository;

// Mention the @Transactional annotation over the service layer method

        @Transactional

public FlightBookingAcknowledgement bookFlightTicket(FlightBookingRequest request) {

PassengerInfo passengerInfo = request.getPassengerInfo();

passengerInfo = passengerInfoRepository.save(passengerInfo);

PaymentInfo paymentInfo = request.getPaymentInfo();

PaymentUtils.validateCreditLimit(paymentInfo.getAccountNo(), passengerInfo.getFare());

paymentInfo.setPassengerId(passengerInfo.getpId());

paymentInfo.setAmount(passengerInfo.getFare());

paymentInfoRepository.save(paymentInfo);

return new FlightBookingAcknowledgement("SUCCESS", passengerInfo.getFare(),

UUID.randomUUID().toString().split("-")[0], passengerInfo);

}

}

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import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

import org.springframework.transaction.annotation.EnableTransactionManagement;

import org.springframework.web.bind.annotation.PostMapping;

import org.springframework.web.bind.annotation.RequestBody;

import org.springframework.web.bind.annotation.RestController;

import com.javaTechie.flightserviceexample.dto.FlightBookingAcknowledgement;

import com.javaTechie.flightserviceexample.dto.FlightBookingRequest;

import com.javaTechie.flightserviceexample.service.FlightBookingService;

//Mention the @EnableTransactionManagement over the Main class of application

@SpringBootApplication

@RestController

@EnableTransactionManagement

public class FlightServiceExampleApplication {

@Autowired

private FlightBookingService service;

@PostMapping("/bookFlightTicket")

public FlightBookingAcknowledgement bookFlightTicket(@RequestBody FlightBookingRequest request ) {

return service.bookFlightTicket(request);

}

public static void main(String[] args) {

SpringApplication.run(FlightServiceExampleApplication.class, args);

}

}