@Entity
@Table(name="emp")
public class Employee implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
@Column(name="emp_id")
private int id;
@Column(name="emp_name")
private String name;
@Column(name="salary")
private int Salary;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getSalary() {
return Salary;
}
public void setSalary(int salary) {
this.Salary = salary;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
}
public enum HibernateUtil {
INSTANCE;
HibernateUtil(){
buildSessionFactory();
}
private SessionFactory sessionFactory=null;
public SessionFactory getSessionFactory() {
return sessionFactory;
}
public void setSessionFactory(SessionFactory sessionFactory) {
this.sessionFactory = sessionFactory;
}
private void buildSessionFactory() {
Configuration configuration = new Configuration();
configuration.addAnnotatedClass (TestRefresh_Merge.Employee.class);
configuration.setProperty("connection.driver_class","com.mysql.jdbc.Driver");
configuration.setProperty("hibernate.connection.url", "jdbc:mysql://localhost:3306/hibernate");
configuration.setProperty("hibernate.connection.username", "root");
configuration.setProperty("hibernate.connection.password", "root");
configuration.setProperty("dialect", "org.hibernate.dialect.MySQLDialect");
configuration.setProperty("hibernate.hbm2ddl.auto", "update");
configuration.setProperty("hibernate.show_sql", "true");
configuration.setProperty(" hibernate.connection.pool_size", "10");
/* configuration.setProperty(" hibernate.cache.use_second_level_cache", "true");
configuration.setProperty(" hibernate.cache.use_query_cache", "true");
configuration.setProperty(" cache.provider_class", "org.hibernate.cache.EhCacheProvider");
configuration.setProperty("hibernate.cache.region.factory_class" ,"org.hibernate.cache.ehcache.EhCacheRegionFactory");
*/
// configuration
StandardServiceRegistryBuilder builder = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties());
sessionFactory = configuration.buildSessionFactory(builder.build());
setSessionFactory(sessionFactory);
}
public static SessionFactory getSessionFactoryInstance(){
return INSTANCE.getSessionFactory();
}
}
public class Main {
public static void main(String[] args) {
HibernateUtil util=HibernateUtil.INSTANCE;
SessionFactory factory=util.getSessionFactory();
//save(factory);
retrieve(factory);
}
private static void retrieve(SessionFactory factory) {
Session sessionOne=factory.openSession();
Employee employee=(Employee)sessionOne.get(Employee.class, 5);
sessionOne.close(); // detached Entity
employee.setName("Deepak1");
Session sessionTwo=factory.openSession();
Employee employee1=(Employee)sessionTwo.get(Employee.class, 5);
sessionTwo.beginTransaction();
sessionTwo.saveOrUpdate(employee); // it will throw exception
//sessionTwo.merge(employee); // it will work
sessionTwo.getTransaction().commit();
sessionTwo.close();
}
private static void save(SessionFactory factory) {
Session sessionOne=factory.openSession();
Employee emp=new Employee();
emp.setName("Abhi");
emp.setSalary(10000);
sessionOne.beginTransaction();
try{
sessionOne.save(emp);
sessionOne.getTransaction().commit();
}catch(Exception e){
e.printStackTrace();
}finally{
sessionOne.close();
}
}
}