SpringJPA – save/retrieve Files/Images to MySQL database with @Lob annotation

In the tutorial, JavaSampleApproach will show you how to create a SpringBoot project that uses SpringJpa with @Lob annotation to save Files/Images to MySQL database.

I. Technologies

– Java 1.8
– Maven 3.6.1
– Spring Tool Suite – Version 3.9.0.RELEASE
– MySQL
– Spring Boot – 1.5.9.RELEASE

II. Goal

– We create a SpringBoot project to save files/images to MySQL database as below structure:

Create MySQL table:

-> Run and check results:

III. Practice

Step to do:
– Create SpringBoot project
– Create data model
– Create JPA Repository
– Implement Client to save/retrieve files/images
– Configure JPA connection & MySQL script

1. Create SpringBoot project

Using SpringToolSuite to create a SpringBoot project with dependencies:

	org.springframework.boot
	spring-boot-starter-data-jpa



	mysql
	mysql-connector-java
	runtime

2. Create data model

package com.javasampleapproach.saveimage2mysql.model;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Lob;
import javax.persistence.Table;

@Entity
@Table(name="image_model")
public class ImageModel {
	@Id
    @Column(name = "id")
    private Long id;
	
    @Column(name = "name")
	private String name;
    
    @Column(name = "type")
	private String type;
	
	@Lob
    @Column(name="pic")
    private byte[] pic;
	
	public ImageModel(){}
	
	public ImageModel(long id, String name, String type, byte[] pic){
		this.id = id;
		this.name = name;
		this.type = type;
		this.pic = pic;
	}
	
	public Long getId(){
		return this.id;
	}
	
	public void setId(Long id){
		this.id = id;
	}
	
	public String getName(){
		return this.name;
	}
	
	public void setName(String name){
		this.name = name;
	}
	
	public String getType(){
		return this.type;
	}
	
	public void setType(String type){
		this.type = type;
	}
	
	public byte[] getPic(){
		return this.pic;
	}
	
	public void setPic(byte[] pic){
		this.pic = pic;
	}
}

3. Create JPA Repository

package com.javasampleapproach.saveimage2mysql.jpa;

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

import com.javasampleapproach.saveimage2mysql.model.ImageModel;

public interface ImageRepository extends JpaRepository{
}

4. Implement Client to save/retrieve files/images

Implement code to save/retrieve files/images from MySQL database via SpringJPA repository:

package com.javasampleapproach.saveimage2mysql;

import java.nio.file.Files;
import java.nio.file.Paths;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.core.io.ClassPathResource;

import com.javasampleapproach.saveimage2mysql.jpa.ImageRepository;
import com.javasampleapproach.saveimage2mysql.model.ImageModel;

@SpringBootApplication
public class SpringJpaSaveImage2MySqlApplication implements CommandLineRunner{

	@Autowired
	ImageRepository imageRepository;
	
	public static void main(String[] args) {
		SpringApplication.run(SpringJpaSaveImage2MySqlApplication.class, args);
	}

	@Override
	public void run(String... arg0) throws Exception {
		// image 1
		ClassPathResource backImgFile = new ClassPathResource("image/jsa_about_img_black_background.png");
		byte[] arrayPic = new byte[(int) backImgFile.contentLength()];
		backImgFile.getInputStream().read(arrayPic);
		ImageModel blackImage = new ImageModel(1, "JSA-ABOUT-IMAGE-BLACK-BACKGROUND", "png", arrayPic);
		
		// image 2
		ClassPathResource blueImgFile = new ClassPathResource("image/jsa_about_img_blue_background.png");
		arrayPic = new byte[(int) blueImgFile.contentLength()];
		blueImgFile.getInputStream().read(arrayPic);
		ImageModel blueImage = new ImageModel(2, "JSA-ABOUT-IMAGE-BLUE-BACKGROUND", "png", arrayPic);
		
		// store image to MySQL via SpringJPA
		imageRepository.save(blackImage);
		imageRepository.save(blueImage);
		
		// retrieve image from MySQL via SpringJPA
		for(ImageModel imageModel : imageRepository.findAll()){
			Files.write(Paths.get("retrieve-dir/" + imageModel.getName() + "." + imageModel.getType()), imageModel.getPic());
		}
	}
}

5. Configure JPA connection & MySQL script

5.1 Configure connection info

– Open application.properties file, add connection info:

spring.datasource.url=jdbc:mysql://localhost:3306/testdb?useSSL=false
spring.datasource.username=root
spring.datasource.password=12345

5.2 MySQL script

– Implement MySQL creating table script:

CREATE TABLE image_model(
   id BIGINT NOT NULL,
   name VARCHAR(100) NOT NULL,
   type VARCHAR(10) NOT NULL,
   pic BLOB NOT NULL,
   PRIMARY KEY (id)
);

IV. Sourcecode

SpringJpaSaveImage2MySql

Last updated on May 18, 2019.