To save an image into database, you need to define a table column as blob data type in MySQL, or equivalent binary type in others database. In Hibernate side, you can declare a byte array variable to store the image data.

Download this example – Hibernate-Image-Example.zip

Here’s an Maven project to use Hibernate to save an image into MySQL ‘avatar‘ table.

1. Table creation

An avatar table creation script in MySQL.

CREATE TABLE  `mkyong`.`avatar` (
  `AVATAR_ID` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
  `IMAGE` BLOB NOT NULL,
  PRIMARY KEY (`AVATAR_ID`) USING BTREE
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

2. Maven dependency

Add Hibernate and MySQL dependency.

pom.xml

<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 
  http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.mkyong.common</groupId>
  <artifactId>HibernateExample</artifactId>
  <packaging>jar</packaging>
  <version>1.0-SNAPSHOT</version>
  <name>HibernateExample</name>
  <url>http://maven.apache.org</url>
  <dependencies>
 
        <dependency>
               <groupId>junit</groupId>
               <artifactId>junit</artifactId>
               <version>3.8.1</version>
               <scope>test</scope>
        </dependency>
 
        <!-- MySQL database driver -->
	<dependency>
		<groupId>mysql</groupId>
		<artifactId>mysql-connector-java</artifactId>
		<version>5.1.9</version>
	</dependency>
 
	<!-- Hibernate framework -->
	<dependency>
		<groupId>hibernate</groupId>
		<artifactId>hibernate3</artifactId>
		<version>3.2.3.GA</version>
	</dependency>
 
	<!-- Hibernate library dependecy start -->
	<dependency>
		<groupId>dom4j</groupId>
		<artifactId>dom4j</artifactId>
		<version>1.6.1</version>
	</dependency>
 
	<dependency>
		<groupId>commons-logging</groupId>
		<artifactId>commons-logging</artifactId>
		<version>1.1.1</version>
	</dependency>
 
	<dependency>
		<groupId>commons-collections</groupId>
		<artifactId>commons-collections</artifactId>
		<version>3.2.1</version>
	</dependency>
 
	<dependency>
		<groupId>cglib</groupId>
		<artifactId>cglib</artifactId>
		<version>2.2</version>
	</dependency>
	<!-- Hibernate library dependecy end -->
 
  </dependencies>
</project>

3. Avatar Model

Create a model class to store the avatar data. The image data type is array of bytes.

Avatar.java

package com.mkyong.common;
 
public class Avatar implements java.io.Serializable {
 
	private Integer avatarId;
	private byte[] image;
 
	public Avatar() {
	}
 
	public Avatar(byte[] image) {
		this.image = image;
	}
 
	public Integer getAvatarId() {
		return this.avatarId;
	}
 
	public void setAvatarId(Integer avatarId) {
		this.avatarId = avatarId;
	}
 
	public byte[] getImage() {
		return this.image;
	}
 
	public void setImage(byte[] image) {
		this.image = image;
	}
 
}

4. Mapping file

Create a Hibernate mapping file for avatar. The data type for image is binary.

Avatar.hbm.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
 
<hibernate-mapping>
    <class name="com.mkyong.common.Avatar" table="avatar" catalog="mkyong">
        <id name="avatarId" type="java.lang.Integer">
            <column name="AVATAR_ID" />
            <generator class="identity" />
        </id>
        <property name="image" type="binary">
            <column name="IMAGE" not-null="true" />
        </property>
    </class>
</hibernate-mapping>

5. Hibernate configuration file

Hibernate configuration file to define the database connection and Hibernate mapping file.

hibernate.cfg.xml

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
    <session-factory>
        <property name="hibernate.bytecode.use_reflection_optimizer">false</property>
        <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="hibernate.connection.password">password</property>
        <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/mkyong</property>
        <property name="hibernate.connection.username">root</property>
        <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
        <property name="show_sql">true</property>
        <mapping resource="com/mkyong/common/Avatar.hbm.xml"></mapping>
    </session-factory>
</hibernate-configuration>

6. Hibernate utility

A Hibernate utility class to get the database connection.

HibernateUtil.java

package com.mkyong.persistence;
 
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
 
public class HibernateUtil {
 
    private static final SessionFactory sessionFactory = buildSessionFactory();
 
    private static SessionFactory buildSessionFactory() {
        try {
            // Create the SessionFactory from hibernate.cfg.xml
            return new Configuration().configure().buildSessionFactory();
        }
        catch (Throwable ex) {
            // Make sure you log the exception, as it might be swallowed
            System.err.println("Initial SessionFactory creation failed." + ex);
            throw new ExceptionInInitializerError(ex);
        }
    }
 
    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
 
    public static void shutdown() {
    	// Close caches and connection pools
    	getSessionFactory().close();
    }
 
}

7. Run it

Read a file “C:\\mavan-hibernate-image-mysql.gif” and save it into database, later get it from database and save it into another image file “C:\\test.gif“.

package com.mkyong.common;
 
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
 
import org.hibernate.Session;
import com.mkyong.persistence.HibernateUtil;
 
public class App 
{
    public static void main( String[] args )
    {
        System.out.println("Hibernate save image into database");
        Session session = HibernateUtil.getSessionFactory().openSession();
 
        session.beginTransaction();
 
        //save image into database
    	File file = new File("C:\\mavan-hibernate-image-mysql.gif");
        byte[] bFile = new byte[(int) file.length()];
 
        try {
	     FileInputStream fileInputStream = new FileInputStream(file);
	     //convert file into array of bytes
	     fileInputStream.read(bFile);
	     fileInputStream.close();
        } catch (Exception e) {
	     e.printStackTrace();
        }
 
        Avatar avatar = new Avatar();
        avatar.setImage(bFile);
 
        session.save(avatar);
 
        //Get image from database
        Avatar avatar2 = (Avatar)session.get(Avatar.class, avatar.getAvatarId());
        byte[] bAvatar = avatar2.getImage();
 
        try{
            FileOutputStream fos = new FileOutputStream("C:\\test.gif"); 
            fos.write(bAvatar);
            fos.close();
        }catch(Exception e){
            e.printStackTrace();
        }
 
        session.getTransaction().commit();
    }
}

Done.

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