Class sorting JSON by ID instead of highest value-CodePudding

I'm doing a vote counting system, the winner is the one who has more than 3 votes, however, I'm facing the following problem. When there is more than one place with 3 votes, instead of my JSON returning the one with the most votes, it always returns the one with more than 3 votes ordered by ID. That is, if the restaurant with ID 1 has 3 votes, and the restaurant with ID 2 has 10 votes, the restaurant with ID 1 ends up appearing on the route /restaurants/winner despite not being the most voted, is there any way I can make the most voted show up?

e.g: return from /restaurants/winner route

{
    "id": 1,
    "restaurant": "Burger King",
    "address": "Av. Ipiranga, 1600",
    "website": "https://www.burgerking.com.br/",
    "description": "Rede de fast-food famosa com hambúrgueres grelhados, batata frita e milk-shakes.",
    "count": 3
}

While McDonalds has 5 votes

{
    "id": 2,
    "restaurant": "McDonalds",
    "address": "Av. Ipiranga, 5200",
    "website": "https://www.mcdonalds.com.br/",
    "description": "Rede de fast-food tradicional conhecida por ter ótimos hambúrgueres e batatas fritas.",
    "count": 5
}

Here are the classes that I'm using:

Restaurant.java

package com.dbserver.restaurantes.entities;

import java.util.HashSet;
import java.util.Set;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;

import com.fasterxml.jackson.annotation.JsonIgnore;

@Entity
@Table(name = "db_restaurants")
public class Restaurant {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String restaurant;
    private String address;
    private String website;
    private String description;
    private Integer count;

    @JsonIgnore
    @OneToMany(mappedBy = "id.restaurant")
    private Set<Vote> votes = new HashSet<>();

    public Restaurant() {
    }

    public Restaurant(Long id, String restaurant, String address, String website, String description, Integer count) {
        this.id = id;
        this.restaurant = restaurant;
        this.address = address;
        this.website = website;
        this.description = description;
        this.count = count;
    }

    public Long getId() {
        return id;
    }

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

    public String getRestaurant() {
        return restaurant;
    }

    public void setRestaurant(String restaurant) {
        this.restaurant = restaurant;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public String getWebsite() {
        return website;
    }

    public void setWebsite(String website) {
        this.website = website;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public Integer getCount() {
        return count;
    }

    public void setCount(Integer count) {
        this.count = count;
    }

    public Set<Vote> getVotes() {
        return votes;
    }

}

RestaurantDTO.java

package com.dbserver.restaurantes.dto;

import com.dbserver.restaurantes.entities.Restaurant;

public class RestaurantDTO {
    private Long id;
    private String restaurant;
    private String address;
    private String website;
    private String description;
    private Integer count;

    public RestaurantDTO() {
    }

    public RestaurantDTO(Long id, String restaurant, String address, String website, String description, Integer count) {
        this.id = id;
        this.restaurant = restaurant;
        this.address = address;
        this.website = website;
        this.description = description;
        this.count = count;
    }

    public RestaurantDTO(Restaurant restaurantDTO) {
        id = restaurantDTO.getId();
        restaurant = restaurantDTO.getRestaurant();
        address = restaurantDTO.getAddress();
        website = restaurantDTO.getWebsite();
        description = restaurantDTO.getDescription();
        count = restaurantDTO.getCount();
    }

    public Long getId() {
        return id;
    }

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

    public String getRestaurant() {
        return restaurant;
    }

    public void setRestaurant(String restaurant) {
        this.restaurant = restaurant;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public String getWebsite() {
        return website;
    }

    public void setWebsite(String website) {
        this.website = website;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }
    
    public Integer getCount() {
        return count;
    }

    public void setCount(Integer count) {
        this.count = count;
    }   
}

RestaurantServices.java

package com.dbserver.restaurantes.services;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import com.dbserver.restaurantes.dto.RestaurantDTO;
import com.dbserver.restaurantes.entities.Restaurant;
import com.dbserver.restaurantes.exceptions.NotFoundException;
import com.dbserver.restaurantes.repositories.RestaurantRepository;

@Service
public class RestaurantServices {

    @Autowired
    private RestaurantRepository repository;

    @Transactional(readOnly = true)
    public Page<RestaurantDTO> findAll(Pageable pageable) {
        Page<Restaurant> result = repository.findAll(pageable);
        Page<RestaurantDTO> page = result.map(x -> new RestaurantDTO(x));
        return page;
    }

    @Transactional(readOnly = true)
    public RestaurantDTO findById(Long id) {
        Restaurant result = repository.findById(id).get();
        RestaurantDTO dto = new RestaurantDTO(result);
        return dto;
    }

    @Transactional(readOnly = true)
    public Restaurant findWinner(Integer count) {
        List<Restaurant> restaurants = repository.findAll();

        for (Restaurant restaurant : restaurants) {
            // Hibernate.initialize(restaurant.getCount());
            if (restaurant.getCount() >= 3) {
                return restaurant;
            }
        }
        throw new NotFoundException(
                "Nenhum restaurante ganhou a votação, é necessário um total de 3 votos para ter um restaurante vencedor.");
    }   

    @Transactional
    public Restaurant addRestaurant(Restaurant newRestaurant) {
        return repository.saveAndFlush(newRestaurant);
    }

}

RestaurantRepository.java

package com.dbserver.restaurantes.repositories;

import org.springframework.data.jpa.repository.JpaRepository;

import com.dbserver.restaurantes.entities.Restaurant;

public interface RestaurantRepository extends JpaRepository<Restaurant, Long> {

}

RestaurantController.java

package com.dbserver.restaurantes.controllers;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.dbserver.restaurantes.dto.RestaurantDTO;
import com.dbserver.restaurantes.entities.Restaurant;
import com.dbserver.restaurantes.services.RestaurantServices;

@RestController
@RequestMapping(value = "/restaurants")
public class RestaurantController {

    @Autowired
    private RestaurantServices service;

    @GetMapping
    public Page<RestaurantDTO> findAll(Pageable pageable) {
        return service.findAll(pageable);
    }

    @GetMapping(value = "/{id}")
    public RestaurantDTO findById(@PathVariable Long id) {
        return service.findById(id);
    }
    
    @GetMapping(value = "/winner")
    public Restaurant findWinner(Integer count) {
        return service.findWinner(count);     
    };

    @PostMapping
    public Restaurant addRestaurant(@RequestBody Restaurant newRestaurant) {
        return service.addRestaurant(newRestaurant);
    }
    
}

CodePudding user response：

You have to check the top value as well. So You need to add your own query for that. Here is the code


public interface RestaurantRepository extends JpaRepository<Restaurant, Long>
{

    Optional<Restaurant> findFirstByCountGreaterThanEqualOrderByCountDesc (Integer count);

}

and Use that inside your method

@Transactional(readOnly = true)
    public Restaurant findWinner(Integer count) throws NotFoundException
    {
        Optional<Restaurant> data = repository.findFirstByCountGreaterThanEqualOrderByCountDesc(3);
        if (data.isPresent())
        {
            return data.get();
        }

        throw new NotFoundException("Nenhum restaurante ganhou a votação, é necessário um total de 3 votos para ter um restaurante vencedor.");
    }

You can use native queries as well.