Build CRUD RESTful API Using Spring Boot 3, Spring Data JPA, Hibernate, and MySQL Database
In this tutorial, we will learn how to build CRUD RESTful API using Spring Boot 3, Spring Data JPA (Hibernate), and MySQL database.
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Join For FreeIn this tutorial, we will learn how to build CRUD RESTful API using Spring Boot 3, Spring Data JPA (Hibernate), and MySQL database.
Note that in this tutorial, we are using the latest Spring Boot version 3.0.0.
Learn complete Spring boot at Learn and Master Spring Boot
Spring Boot Project Architecture
We are going to use three-layer architecture in our Spring Boot project:
Tools and Technologies Used:
- Spring Boot 3.0
- Java 17
- Spring Data JPA
- Hibernate
- MySQL Database
- Maven
- Postman
Create and Setup Spring Boot Project in IntelliJ
Spring Boot provides a web tool called Spring Initializer to create and bootstrap Spring Boot applications quickly. Just go here and generate a new Spring Boot project.
Refer to this screenshot to enter the details to create the Spring Boot project:
Here is the pom.xml file for your reference:
<?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>3.0.0</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>net.javaguides</groupId>
<artifactId>springboot-restful-webservices</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>springboot-restful-webservices</name>
<description>Demo project for Spring Boot Restful Webservices</description>
<properties>
<java.version>17</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>com.mysql</groupId>
<artifactId>mysql-connector-j</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<excludes>
<exclude>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</exclude>
</excludes>
</configuration>
</plugin>
</plugins>
</build>
</project>Project Structure
Refer to this screenshot to create a project structure:
Configure MySQL Database
Let's first create a database, go to MySQL workbench, and use the below SQL query to create a new database:
create database user_managementNext, open the application.propertiesfile and add the following properties to it.
spring.datasource.url=jdbc:mysql://localhost:3306/user_management
spring.datasource.username=root
spring.datasource.password=Mysql@123
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQLDialect
spring.jpa.hibernate.ddl-auto=updateMake sure that you change the spring.datasource.username & spring.datasource.password properties as per your MySQL installation.
In the above properties file, the last two properties are for Hibernate. Spring Boot uses Hibernate as the default JPA implementation.
The property spring.jpa.hibernate.ddl-auto is used for database initialization. I’ve used the value “update” for this property to create the database tables automatically.
Create User JPA Entity
Let's create a User class and add the following content to it:
package net.javaguides.springboot.entity;
import jakarta.persistence.*;
import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.NoArgsConstructor;
import lombok.Setter;
@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@Entity
@Table(name = "users")
public class User {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
@Column(nullable = false)
private String firstName;
@Column(nullable = false)
private String lastName;
@Column(nullable = false, unique = true)
private String email;
}Note that we are using Lombok annotations to reduce the boilerplate code (getters/setters).
Create Spring Data JPA Repository — UserRepository
Let's create a UserRepository interface that extends JpaRepository:
package net.javaguides.springboot.repository;
import net.javaguides.springboot.entity.User;
import org.springframework.data.jpa.repository.JpaRepository;
public interface UserRepository extends JpaRepository<User, Long> {
}Note that we do not need to add @Repository annotation because Spring Data JPA internally takes care of it.
Create Service Layer
Service Interface
Let's create an UserService interface and declare the following CRUD methods:
package net.javaguides.springboot.service;
import net.javaguides.springboot.entity.User;
import java.util.List;
public interface UserService {
User createUser(User user);
User getUserById(Long userId);
List<User> getAllUsers();
User updateUser(User user);
void deleteUser(Long userId);
}UserServiceImpl Class
Let's create UserServiceImpl class that implements UserService interface methods:
package net.javaguides.springboot.service.impl;
import lombok.AllArgsConstructor;
import net.javaguides.springboot.entity.User;
import net.javaguides.springboot.repository.UserRepository;
import net.javaguides.springboot.service.UserService;
import org.apache.logging.log4j.util.Strings;
import org.springframework.stereotype.Service;
import org.springframework.util.StringUtils;
import java.util.List;
import java.util.Objects;
import java.util.Optional;
@Service
@AllArgsConstructor
public class UserServiceImpl implements UserService {
private UserRepository userRepository;
@Override
public User createUser(User user) {
return userRepository.save(user);
}
@Override
public User getUserById(Long userId) {
Optional<User> optionalUser = userRepository.findById(userId);
return optionalUser.get();
}
@Override
public List<User> getAllUsers() {
return userRepository.findAll();
}
@Override
public User updateUser(User user) {
User existingUser = userRepository.findById(user.getId()).get();
existingUser.setFirstName(user.getFirstName());
existingUser.setLastName(user.getLastName());
existingUser.setEmail(user.getEmail());
User updatedUser = userRepository.save(existingUser);
return updatedUser;
}
@Override
public void deleteUser(Long userId) {
userRepository.deleteById(userId);
}
}Create Controller Layer — UserController
We’ll now create the REST APIs for creating, retrieving, updating, and deleting a User resource.
Let's create UserController class and let's build CRUD REST API's for User resource:
package net.javaguides.springboot.controller;
import lombok.AllArgsConstructor;
import net.javaguides.springboot.entity.User;
import net.javaguides.springboot.service.UserService;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
import java.util.List;
@RestController
@AllArgsConstructor
@RequestMapping("api/users")
public class UserController {
private UserService userService;
// build create User REST API
@PostMapping
public ResponseEntity<User> createUser(@RequestBody User user){
User savedUser = userService.createUser(user);
return new ResponseEntity<>(savedUser, HttpStatus.CREATED);
}
// build get user by id REST API
// http://localhost:8080/api/users/1
@GetMapping("{id}")
public ResponseEntity<User> getUserById(@PathVariable("id") Long userId){
User user = userService.getUserById(userId);
return new ResponseEntity<>(user, HttpStatus.OK);
}
// Build Get All Users REST API
// http://localhost:8080/api/users
@GetMapping
public ResponseEntity<List<User>> getAllUsers(){
List<User> users = userService.getAllUsers();
return new ResponseEntity<>(users, HttpStatus.OK);
}
// Build Update User REST API
@PutMapping("{id}")
// http://localhost:8080/api/users/1
public ResponseEntity<User> updateUser(@PathVariable("id") Long userId,
@RequestBody User user){
user.setId(userId);
User updatedUser = userService.updateUser(user);
return new ResponseEntity<>(updatedUser, HttpStatus.OK);
}
// Build Delete User REST API
@DeleteMapping("{id}")
public ResponseEntity<String> deleteUser(@PathVariable("id") Long userId){
userService.deleteUser(userId);
return new ResponseEntity<>("User successfully deleted!", HttpStatus.OK);
}
}
Running Spring Boot Application
Run the Spring Boot Application From IDE:
From your IDE, run the SpringbootRestfulWebservicesApplication.main() method as a standalone Java class that will start the embedded Tomcat server on port 8080 and point the browser here.
Run the Spring Boot Application Using the Command Line:
Just go to the root directory of the application and type the following command to run it:
$ mvn spring-boot:runThe application will start at Spring Boot’s default tomcat port 8080.
Test CRUD RESTful WebServices Using Postman Client
Create User REST API
HTTP Method: POST
Request Body:
{
"firstName": "ramesh",
"lastName":"fadatare",
"email": "ramesh@gmail.com"
}Refer to this screenshot to test Create User REST API:
Get User REST API
HTTP Method: GET
Refer to this screenshot to test GET User REST API:
Update User REST API
HTTP Method: PUT
Request Body:
{
"firstName": "ram",
"lastName":"fadatare",
"email": "ram@gmail.com"
}Refer to this screenshot to test the Update User REST API:
Get All Users REST API
HTTP Method: GET
Refer to this screenshot to test GET All User REST API:
DELETE User REST API
HTTP Method: DELETE
Refer to this screenshot to test Delete User REST API:
Source Code on GitHub
The source code of this tutorial is available on my GitHub repository at Spring Boot CRUD RESTful WebServices
Conclusion
In this tutorial, we have created a Spring boot project and built CRUD RESTful Webservices using Spring Boot 3, Spring Data JPA (Hibernate), and MySQL database.
Published at DZone with permission of Ramesh Fadatare. See the original article here.
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