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.
Contents
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:
|
1 2 3 4 5 6 7 8 9 10 |
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> |
2. Create data model
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 |
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
|
1 2 3 4 5 6 7 8 |
package com.javasampleapproach.saveimage2mysql.jpa; import org.springframework.data.jpa.repository.JpaRepository; import com.javasampleapproach.saveimage2mysql.model.ImageModel; public interface ImageRepository extends JpaRepository<ImageModel, Long>{ } |
4. Implement Client to save/retrieve files/images
Implement code to save/retrieve files/images from MySQL database via SpringJPA repository:
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 |
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:
|
1 2 3 |
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:
|
1 2 3 4 5 6 7 |
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) ); |