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Hey guys in this post, we will discuss fetch the single record from the database using Spring JdbcTemplate in Spring Boot.

Overview

• JdbcTemplate is class which will help us to query the database
• queryForObject()is a method provided by JdbcTemplate, which is used to fetch the single record from the database
• queryForObject() takes 3 parameters, sql_query, row_mapper and parameter

Complete Example

We will create this example step by step, follow this tutorial till the end

Read More:

• Check the Complete JavaServer Faces (JSF) Tutorial
• Check the Complete Spring Data JPA Tutorial
• Check the Complete Spring Security Tutorial
• Check the Javascript Projects for Beginners

Create a Database

Open the mysql console or workbench and execute the following queries

CREATE DATABASE springbootjdbc;

USE springbootjdbc;

CREATE TABLE tbl_employees
(
	id INT PRIMARY KEY AUTO_INCREMENT,
    name VARCHAR(255) NOT NULL,
    location VARCHAR(255) NOT NULL,
    dateOfBirth DATETIME NOT NULL
);

INSERT INTO tbl_employees
(name, location, dateOfBirth)
VALUES
("Bushan", "India", now());

INSERT INTO tbl_employees
(name, location, dateOfBirth)
VALUES
("Bharath", "India", now());

Create spring boot project

There are many different ways to create a spring boot application, you can follow the below articles to create one –

>> Create spring boot application using Spring initializer
>> Create spring boot application in Spring tool suite [STS]
>> Create spring boot application in IntelliJ IDEA

Add maven dependencies

Open pom.xml and add the following dependencies –

<?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>2.5.3</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>in.bushansirgur</groupId>
	<artifactId>springbootjdbc</artifactId>
	<version>1.0.0</version>
	<name>springbootjdbc</name>
	<description>Spring boot jdbc project</description>
	<properties>
		<java.version>16</java.version>
	</properties>
	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-jdbc</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-devtools</artifactId>
			<scope>runtime</scope>
			<optional>true</optional>
		</dependency>
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</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>

spring-boot-starter-web dependency for building web applications using Spring MVC. It uses the tomcat as the default embedded container.

spring-boot-devtools dependency for automatic reloads or live reload of applications. spring-boot-starter-jdbc is a starter dependency for communicating with the database. lombok dependency is a java library that will reduce the boilerplate code that we usually write inside every entity class like setters, getters, and toString(). mysql-connector-java dependency is to store the data into the database.

Configure the datasource

Open application.properties file and add the following contents

spring.datasource.url=jdbc:mysql://localhost:3306/springbootjdbc
spring.datasource.username=root
spring.datasource.password=scbushan05

Create an entity class

Create Employee.java inside the in.bushansirgur.springboot.entity package and add the following content

package in.bushansirgur.springbootjdbc.entity;

import java.util.Date;

import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.NoArgsConstructor;
import lombok.Setter;

@Setter
@Getter 
@NoArgsConstructor
@AllArgsConstructor
public class Employee {
	
	private Long id;
	
	private String name;
	
	private String location;
	
	private Date dateOfBirth;
	
	public Employee(String name, String location, Date dateOfBirth) {
		this.name = name;
		this.location = location;
		this.dateOfBirth = dateOfBirth;
	}
}

• @Setter annotation generates the setter methods
• @Getter annotation generates the getter methods
• @AllArgsConstructor generates parameterised constructor with all the fields
• @NoArgsConstructor generates no-arg constructor

Create a DAO

Create an interface EmployeeDAO.java inside the in.bushansirgur.springboot.dao package and add the following content

package in.bushansirgur.springbootjdbc.DAO;

import java.util.List;

import in.bushansirgur.springbootjdbc.entity.Employee;

public interface EmployeeDAO {
	
	public List<Employee> findAll();
	
	public Employee findById(int id);
}

Create EmployeeDAOImpl.java inside the in.bushansirgur.springboot.dao package and add the following content

package in.bushansirgur.springbootjdbc.DAO;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;

import in.bushansirgur.springbootjdbc.entity.Employee;

@Repository
public class EmployeeDAOImpl implements EmployeeDAO{

	@Autowired
	JdbcTemplate jdbcTemplate;
	
	@Override
	public List<Employee> findAll() {
		return jdbcTemplate.query("SELECT * FROM tbl_employees", new BeanPropertyRowMapper<Employee>(Employee.class));
	}

	@Override
	public Employee findById(int id) {
		return jdbcTemplate.queryForObject("SELECT * FROM tbl_employees WHERE id=?", new BeanPropertyRowMapper<Employee>(Employee.class), id);
	}
	
}

Create a Controller

Create EmployeeController.java inside the in.bushansirgur.springbootjdbc.controller package and add the following content

package in.bushansirgur.springbootjdbc.controller;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;

import in.bushansirgur.springbootjdbc.DAO.EmployeeDAO;
import in.bushansirgur.springbootjdbc.entity.Employee;

@RestController
public class EmployeeController {
	
	@Autowired 
	private EmployeeDAO eDAO;
	
	@GetMapping("/employees")
	public List<Employee> findAll() {
		return eDAO.findAll();
	}
	
	@GetMapping("/employees/{id}")
	public Employee findById(@PathVariable int id) {
		return eDAO.findById(id);
	}
}

Run the app

Run the application using the below maven command –

mvn spring-boot:run

Open the Browser or Postman and enter the following URL –

• localhost:8080/employees

—

• localhost:8080/employees/2

That’s it for this post. I hope you enjoyed this post, if you did then please share this with your friends and colleagues. Also, you can share this post with your social media profiles. Thank you I will see you in the next post.