@Entity
@Table(name="OBJECTS")
public class MyEntity {
   
   private Integer objectID;

   @Id
   @Column(name="OBJECT_ID")
   @SequenceGenerator(name="OBJECT_SEQ", sequenceName="OBJECT_SEQ", allocationSize=1)
   @GeneratedValue(strategy=GenerationType.SEQUENCE, generator="OBJECT_SEQ")
   public Integer getObjectID() {
      return ObjectID;
   }
   
   public void setObjectID(Integer objectID) {
      this.objectID = objectID;
   }


   @PrePersist
   public void prePersist()
   {
      System.out.println("In Object");
   }
   
   @PreRemove
   public void preRemove()
   {
      System.out.println("here");
   }
}

<?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>

        <!-- Database connection settings -->
        <property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
        <property name="connection.url">....</property>
        <property name="connection.username">...</property>
        <property name="connection.password">...</property>
       
        <!-- JDBC connection pool (use the built-in) -->
        <property name="connection.pool_size">1</property>

        <!-- SQL dialect -->
        <property name="dialect">org.hibernate.dialect.OracleDialect</property>

        <!-- Enable Hibernate's automatic session context management -->
        <property name="current_session_context_class">thread</property>

        <!-- Disable the second-level cache  -->
        <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>

        <!-- Echo all executed SQL to stdout -->
        <property name="show_sql">false</property>
     
       <mapping class="MyEntity"/>
   
    </session-factory>

</hibernate-configuration>

      AnnotationConfiguration conf = new AnnotationConfiguration();
      SessionFactory sessionFactory = conf.configure().buildSessionFactory();
      Session session = sessionFactory.openSession();
      session.persist(new MyEntity());
      session.flush();
      session.close();

      Ejb3Configuration conf = new Ejb3Configuration();
      EntityManagerFactory emf = conf.configure("hibernate.cfg.xml").buildEntityManagerFactory();
      EntityManager em = emf.createEntityManager();
       em.persist(new MyEntity());
       em.close();