Utilisation de Spring - CRUD

Bonjour,

J'essaye de mieux comprendre comment fonctionne Spring. Mon projet Java se découpe de la manière suivante :

-com.exemple.demo
->DemoApplication.java
->UserController.java
-com.exemple.demo.bo
->User.java
-com.exemple.demo.config
->ApplicationConfig.java
-com.exemple.demo.dal
->UserService.java
->UserServiceImpl.java
-com.exemple.demo.dao
->UserDao.java

Problème : je n'arrive pas à accéder à localhost:8088/users défini dans le controller. J'obtiens cette erreur : Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.

Voici mes classes :

pom.xml :

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.4.5</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.example</groupId>
	<artifactId>demo</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>demo</name>
	<description>Demo project for Spring Boot</description>
	<properties>
		<java.version>11</java.version>
	</properties>
	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-data-mongodb-reactive</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
		<dependency>
			<groupId>io.projectreactor</groupId>
			<artifactId>reactor-test</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>

</project>

DemoApplication :

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;

@SpringBootApplication
@ComponentScan(basePackages = {"com.example.demo.dao"})
public class DemoApplication {

	public static void main(String[] args) {
		SpringApplication.run(DemoApplication.class, args);
	}

	
} 

UserController :

package com.example.demo;

import java.util.Collection;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.http.HttpStatus;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseStatus;
import org.springframework.web.bind.annotation.RestController;

import com.example.demo.bo.User;
import com.example.demo.dal.UserService;

@RestController
@RequestMapping("/users")
public class UserController {

	@Autowired
	@Qualifier(value = "userService")
	UserService userv;

	private final Logger logger = LoggerFactory.getLogger(this.getClass());

	@GetMapping(value="")
	@ResponseStatus(HttpStatus.OK)
	public Collection<User> getAll(){
		System.out.println("----->getAll");
		logger.debug("Getting all users.");
		return userv.getAllUsers();
	}
}

User :

package com.example.demo.bo;

import org.springframework.data.annotation.Id;
import org.springframework.data.mongodb.core.mapping.Document;

@Document(collection="user")
public class User {
	
	@Id
	private int id;
	private String nom;
	private String prenom;
	private String age;
	
	
	public int getId(){
		return id;
	}
	
	public String getNom(){
		return nom;
	}
	
	public String getPrenom(){
		return prenom;
	}
	
	public String getAge(){
		return age;
	}
	
	public void setId(int id) {
		this.id = id;
	}
	
	public void setNom(String nom) {
		this.nom = nom;
	}
	
	public void setPrenom(String prenom) {
		this.prenom = prenom;
	}
	
	public void setAge(String age) {
		this.age = age;
	}

	@Override
	public String toString(){
		return "User [id=" + id + ", nom=" + nom + ", prenom=" + prenom + ", age=" + age + "]";
	}	

}

ApplicationConfig :

package com.example.demo.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;

import com.example.demo.dal.UserService;
import com.example.demo.dal.UserServiceImpl;

@Configuration
@ComponentScan("com.exemple.demo")
public class ApplicationConfig {

	@Bean(name = "userService")
	public UserService getTopoService(){
		return new UserServiceImpl();
	}

}

UserService :

package com.example.demo.dal;

import java.util.Collection;
import java.util.List;
import java.util.Optional;

import org.springframework.stereotype.Service;

import com.example.demo.bo.User;

@Service
public interface UserService {
	
	public void createUser(List<User> user);
	public Collection<User> getAllUsers();
	public Optional<User> findUserById(int id);
	public void deleteUserById (int id);
	public void updateUser (User user);
	public void deleteAllUsers();
	

}

UserServiceImpl :

package com.example.demo.dal;

import java.util.Collection;
import java.util.List;
import java.util.Optional;

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

import com.example.demo.bo.User;
import com.example.demo.dao.UserDao;

@Component
public class UserServiceImpl implements UserService {
	
	@Autowired
	UserDao dao;

	@Override
	public void createUser(List<User> user) {
		dao.saveAll(user);	
	}

	@Override
	public Collection<User> getAllUsers(){
		return dao.findAll();
	}

	@Override
	public Optional<User> findUserById(int id) {
		return dao.findById(id);
	}

	@Override
	public void deleteUserById(int id) {
		dao.deleteById(id);	
	}

	@Override
	public void updateUser(User user) {
		dao.save(user);	
	}

	@Override
	public void deleteAllUsers(){
		dao.deleteAll();
		
	}

}

UserDao :

package com.example.demo.dao;

import org.springframework.data.mongodb.repository.MongoRepository;
import org.springframework.stereotype.Repository;

import com.example.demo.bo.User;

@Repository
public interface UserDao extends MongoRepository<User, Integer> {


}