Effortless CRUD Operations with Spring Boot and MySQL: A Step-by-Step Guide

CRUD OPERATION: SPRING BOOT, MYSQL, HIBERNATE, POSTMAN

👉 FOLLOW THESE STEPS

Step 1: 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>2.7.1</version>
            <relativePath/> <!-- lookup parent from repository -->
        </parent>
        <groupId>com.heycolleagues</groupId>
        <artifactId>CRUD-OPERATION</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <name>CRUD-OPERATION</name>
        <description>CRUD OPERATION BY HEY COLLEAGUES</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>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <scope>runtime</scope>
            </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>
                </plugin>
            </plugins>
        </build>
    
    </project>
    

Step 2: application.properties

    # MySQL connection
    server.port=9091
    spring.datasource.url=jdbc:mysql://localhost:3306/projectcrud
    spring.datasource.username=root
    spring.datasource.password=root
    
    # hibernate Configuration
    spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL8Dialect
    spring.jpa.hibernate.ddl-auto=update
    spring.jpa.show-sql=true
    spring.jpa.properties.hibernate.format_sql=true

Step 3: class- CrudOperationApplication.java

    package com.heycolleagues;

    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    @SpringBootApplication
    public class CrudOperationApplication {
    
        public static void main(String[] args) {
            SpringApplication.run(CrudOperationApplication.class, args);
        }
    
    }
    

Step 4: class- Employee.java

               

    package com.heycolleagues.model;

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

@Entity
public class Employee {
	
	@Id
	@GeneratedValue(strategy = GenerationType.AUTO)
	private Long employeeId;
	
	private String username;
	private String password;
	public Employee(Long employeeId, String username, String password) {
		super();
		this.employeeId = employeeId;
		this.username = username;
		this.password = password;
	}
	public Long getEmployeeId() {
		return employeeId;
	}
	public void setEmployeeId(Long employeeId) {
		this.employeeId = employeeId;
	}
	public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	public Employee() {
		super();
		// TODO Auto-generated constructor stub
	}
	
	

}

Step 5: interface-EmployeeRepository.java

    package com.heycolleagues.repository;

    import org.springframework.data.jpa.repository.JpaRepository;
    import org.springframework.stereotype.Repository;
    
    import com.heycolleagues.model.Employee;
    
    @Repository
    public interface EmployeeRepository extends JpaRepository<Employee, Long>{
        
        public Employee findByUsername(String username);
    
    }
    

Step 6: interface-EmployeeService.java

               

    package com.heycolleagues.service;

import java.util.List;

import com.heycolleagues.model.Employee;


public interface EmployeeService {
	
	public Employee createEmployee(Employee employee);
	public Employee updateEmployee(String username, Employee employee) throws Exception;
	public Employee getEmployeeByUsername(String username);
	public List<Employee> getAllEmployee();
	public void deleteEmployeeById(Long employeeId);

}

Step 7: class-EmployeeServiceImplement.java

               

    package com.heycolleagues.serviceImplement;

import java.util.List;

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

import com.heycolleagues.model.Employee;
import com.heycolleagues.repository.EmployeeRepository;
import com.heycolleagues.service.EmployeeService;

@Service
public class EmployeeServiceImplement implements EmployeeService{
	
	@Autowired
	private EmployeeRepository employeeRepository;

	@Override
	public Employee createEmployee(Employee employee) {
		Employee local = employeeRepository.findByUsername(employee.getUsername());
		if (local == null) {
			System.out.println("Username already taken, \n Try with other username");
		}else {
			local = this.employeeRepository.save(employee);
		}
		return this.employeeRepository.save(employee);
	}

	@Override
	public Employee updateEmployee(String username ,Employee employee) throws Exception {
		Employee local = employeeRepository.findByUsername(username);
		if (local != null) {
			Employee local1 = employeeRepository.findByUsername(employee.getUsername());
			if (local1 != null) {
				throw new Exception("Try with another username for signup \n Thank You!!");
			}else {
				local.setUsername(employee.getUsername());
				local.setPassword(employee.getPassword());
			}
			
			
		}else {
			System.out.println("Please record is founded in our database");
		}
		return this.employeeRepository.save(local);
	}

	@Override
	public Employee getEmployeeByUsername(String username) {
		return this.employeeRepository.findByUsername(username);
	}

	@Override
	public List<Employee> getAllEmployee() {
		return this.employeeRepository.findAll();
	}

	@Override
	public void deleteEmployeeById(Long employeeId) {
		this.employeeRepository.deleteById(employeeId);
		
	}

}

Step 8: class- EmployeeController.class

               


    package com.heycolleagues.controller;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.DeleteMapping;
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.PutMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.heycolleagues.model.Employee;
import com.heycolleagues.serviceImplement.EmployeeServiceImplement;

@RestController
@RequestMapping("/api/v1")
public class EmployeeController {
	
	@Autowired
	private EmployeeServiceImplement serviceImplement;
	
	@PostMapping("/create")
	public ResponseEntity<Employee> createEmployee(@RequestBody Employee employee){
		return ResponseEntity.ok(this.serviceImplement.createEmployee(employee));
	}
	
	@PutMapping("/update/{username}")
	public ResponseEntity<Employee> updateEmployee
	(@PathVariable("username") String username ,@RequestBody Employee employee)
	throws Exception
	{
		return ResponseEntity.ok(this.serviceImplement.updateEmployee(username, employee));
	}
	
	@GetMapping("/get/{username}")
	public Employee getEmployeeByUsername(@PathVariable("username") String username) {
		return this.serviceImplement.getEmployeeByUsername(username);
	}

	@GetMapping("/getAllEmployees")
	public List<Employee> getAllEmployee(){
		return this.serviceImplement.getAllEmployee();
	}
	
	@DeleteMapping("/delete/{employeeId}")
	public void deleteEmployeeById(@PathVariable("employeeId") Long id) {
		this.serviceImplement.deleteEmployeeById(id);
	}
}