Maven 2 + Hibernate 3.2 + MySQL Example (Annotation)

This tutorial will modify the previous Maven 2 + Hibernate 3.2 + MySQL Example (XML mapping), and replace the Hibernate XML mapping file with Annotation code.

Tools & technologies used in this article :

- Maven 2.2.1

- JDK 1.6.0_13

- Hibernate 3.2.3.GA

- MySQL 5.0

1. Create project infrastructure

Create project infrastructure in Maven + Hibernate (XML mapping file) + MySQL Example

2. Add JBoss repository

JBoss repository in

pom.xml

is required to download the Hibernate annotation library.

<repositories>
<repository>
<id>JBoss repository</id>
<url>http://repository.jboss.com/maven2/</url>
</repository>
</repositories>

3. Add Hibernate annotation dependency

Add

hibernate-annotations

and

hibernate-commons-annotations

dependency in

pom.xml

.

<dependency>
<groupId>hibernate-annotations</groupId>
<artifactId>hibernate-annotations</artifactId>
<version>3.3.0.GA</version>
</dependency>

<dependency>
<groupId>hibernate-commons-annotations</groupId>
<artifactId>hibernate-commons-annotations</artifactId>
<version>3.0.0.GA</version>
</dependency>

File :

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>

<repositories>
<repository>
<id>JBoss repository</id>
<url>http://repository.jboss.com/maven2/</url>
</repository>
</repositories>

<dependencies>

<!-- MySQL database driver -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.9</version>
</dependency>

<!-- Hibernate core -->
<dependency>
<groupId>hibernate</groupId>
<artifactId>hibernate3</artifactId>
<version>3.2.3.GA</version>
</dependency>

<!-- Hibernate annotation -->
<dependency>
<groupId>hibernate-annotations</groupId>
<artifactId>hibernate-annotations</artifactId>
<version>3.3.0.GA</version>
</dependency>

<dependency>
<groupId>hibernate-commons-annotations</groupId>
<artifactId>hibernate-commons-annotations</artifactId>
<version>3.0.0.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 -->

<dependency>
<groupId>javax.transaction</groupId>
<artifactId>jta</artifactId>
<version>1.1</version>
</dependency>

</dependencies>
</project>

4. Update project classpath

Issue “

mvn eclipse:eclipse

” in command prompt to download the dependency library and update the Eclipse’s project classpath.

5. Update

HibernateUtil.java

Update “

HibernateUtil

” to use “

AnnotationConfiguration

” instead of “

Configuration

” to build the Hibernate session factory.

Previously is using “

Configuration

” – For Hibernate XML mapping file

return new Configuration().configure().buildSessionFactory();

Change it to “

AnnotationConfiguration

” – For Hibernation annotation support

return new AnnotationConfiguration().configure().buildSessionFactory();

File :

HibernateUtil.java

package com.mkyong.persistence;

import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;

public class HibernateUtil {

private static final SessionFactory sessionFactory = buildSessionFactory();

private static SessionFactory buildSessionFactory() {
try {
// Create the SessionFactory from hibernate.cfg.xml
return new AnnotationConfiguration().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();
}

}

6. Update Model class

Update “

Stock.java

” to use annotation as follow :

Stock.java

package com.mkyong.common;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import static javax.persistence.GenerationType.IDENTITY;
import javax.persistence.Id;
import javax.persistence.Table;
import javax.persistence.UniqueConstraint;

@Entity
@Table(name = "stock", catalog = "mkyong", uniqueConstraints = {
@UniqueConstraint(columnNames = "STOCK_NAME"),
@UniqueConstraint(columnNames = "STOCK_CODE") })
public class Stock implements java.io.Serializable {

private Integer stockId;
private String stockCode;
private String stockName;

public Stock() {
}

public Stock(String stockCode, String stockName) {
this.stockCode = stockCode;
this.stockName = stockName;
}

@Id
@GeneratedValue(strategy = IDENTITY)
@Column(name = "STOCK_ID", unique = true, nullable = false)
public Integer getStockId() {
return this.stockId;
}

public void setStockId(Integer stockId) {
this.stockId = stockId;
}

@Column(name = "STOCK_CODE", unique = true, nullable = false, length = 10)
public String getStockCode() {
return this.stockCode;
}

public void setStockCode(String stockCode) {
this.stockCode = stockCode;
}

@Column(name = "STOCK_NAME", unique = true, nullable = false, length = 20)
public String getStockName() {
return this.stockName;
}

public void setStockName(String stockName) {
this.stockName = stockName;
}

}

7. Delete existing Hibernate XML mapping file

Delete existing Hibernate XML mapping file – “

Stock.hbm.xml

”, this is no longer require.

8. Update Hibernate configuration file

Update the Hibernate configuration file –

hibernate.cfg.xml

.

Previously it had the Hibernate XML mapping file with “

mapping resource

” tag

<mapping resource="com/mkyong/common/Stock.hbm.xml"></mapping>

Change it to model class with “mapping class” tag

<mapping class="com.mkyong.common.Stock"></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 class="com.mkyong.common.Stock"></mapping>
</session-factory>
</hibernate-configuration>

9. Review project structure

Sound like few files were modified, review it and make sure the folder structure as follow :

10. Run it and see output

Run your

App.java

, it will insert a new record into “

Stock

” table. The result should be same with previous Hibernate XML mapping file example.

Maven + Hibernate + MySQL
...
Hibernate: insert into mkyong.stock (STOCK_CODE, STOCK_NAME) values (?, ?)

Done.