hibernate sample code
This section contains a simple Hibernate 4 example using Annotation with source code. The eclipse id and Apache Tomcat is used in this example.
In Hibernate 4, buildSessionFactory( ) is deprecated. This example contains code which you can use in spite of buildSessionFactory ().
The project hierarchy is given below :
The jar file used in this example is given below :
The database query used to create database is :
create table WORKER ( id INT NOT NULL auto_increment, first_name VARCHAR(20) default NULL, last_name VARCHAR(20) default NULL, salary INT default NULL, PRIMARY KEY (id) );
hibernate.cfg.xml
<?xml version='1.0' encoding='utf-8'?> <!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <session-factory> <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property> <property name="hibernate.connection.url">jdbc:mysql://192.168.10.13:3306/ankdb</property> <property name="hibernate.connection.username">root</property> <property name="hibernate.connection.password">root</property> <property name="hibernate.connection.pool_size">10</property> <property name="show_sql">true</property> <property name="dialect">org.hibernate.dialect.MySQLDialect</property> <property name="hibernate.current_session_context_class">thread</property> <mapping class="worker.Worker" /> </session-factory> </hibernate-configuration>
POJO class( Worker.java )
package worker; import javax.persistence.*; @Entity @Table(name = "Worker") public class Worker { @Id @GeneratedValue @Column(name = "id") private int id; @Column(name = "first_name") private String firstName; @Column(name = "last_name") private String lastName; @Column(name = "salary") private int salary; public Worker() { } public Worker(String fname, String lname, int salary) { this.firstName = fname; this.lastName = lname; this.salary = salary; } public int getId() { return id; } public void setId(int id) { this.id = id; } public String getFirstName() { return firstName; } public void setFirstName(String first_name) { this.firstName = first_name; } public String getLastName() { return lastName; } public void setLastName(String last_name) { this.lastName = last_name; } public int getSalary() { return salary; } public void setSalary(int salary) { this.salary = salary; } }
Application class( HandlingWorker.java )
package worker; import java.util.List; import java.util.Iterator; import org.hibernate.HibernateException; import org.hibernate.Session; import org.hibernate.Transaction; import org.hibernate.SessionFactory; import org.hibernate.cfg.Configuration; import org.hibernate.service.ServiceRegistry; import org.hibernate.service.ServiceRegistryBuilder; public class HandlingWorker { private static SessionFactory factory; private static ServiceRegistry serviceRegistry; public static void main(String[] args) { try{ Configuration configuration = new Configuration(); configuration.configure(); serviceRegistry = new ServiceRegistryBuilder().applySettings(configuration.getProperties()).buildServiceRegistry(); factory = configuration.buildSessionFactory(serviceRegistry); }catch (Throwable ex) { System.err.println("Failed to create sessionFactory object." + ex); throw new ExceptionInInitializerError(ex); } HandlingWorker handle = new HandlingWorker(); /* Add few worker records in database */ Integer worker1 = handle.addWorker("Ram", "Prasad", 1000); Integer worker2 = handle.addWorker("Rahul", "Das", 5000); Integer worker3 = handle.addWorker("Steven", "Abraham", 10000); /* List down all the workers */ handle.listWorkers(); /* Update worker's records */ handle.updateWorker(worker1, 5000); /* Delete an worker from the database */ handle.deleteWorker(worker2); /* List down new list of the workers */ handle.listWorkers(); } /* Method to CREATE an worker in the database */ public Integer addWorker(String fname, String lname, int salary){ Session session = factory.openSession(); Transaction tx = null; Integer workerID = null; try{ tx = session.beginTransaction(); Worker worker = new Worker(fname, lname, salary); workerID = (Integer) session.save(worker); tx.commit(); }catch (HibernateException e) { if (tx!=null) tx.rollback(); e.printStackTrace(); }finally { session.close(); } return workerID; } /* Method to READ all the employees */ public void listWorkers( ){ Session session = factory.openSession(); Transaction tx = null; try{ tx = session.beginTransaction(); List employees = session.createQuery("FROM Worker").list(); for (Iterator iterator = employees.iterator(); iterator.hasNext();){ Worker worker = (Worker) iterator.next(); System.out.print("First Name: " + worker.getFirstName()); System.out.print(" Last Name: " + worker.getLastName()); System.out.println(" Salary: " + worker.getSalary()); } tx.commit(); }catch (HibernateException e) { if (tx!=null) tx.rollback(); e.printStackTrace(); }finally { session.close(); } } /* Method to UPDATE salary for an worker */ public void updateWorker(Integer WorkerID, int salary ){ Session session = factory.openSession(); Transaction tx = null; try{ tx = session.beginTransaction(); Worker worker = (Worker)session.get(Worker.class, WorkerID); worker.setSalary( salary ); session.update(worker); tx.commit(); }catch (HibernateException e) { if (tx!=null) tx.rollback(); e.printStackTrace(); }finally { session.close(); } } /* Method to DELETE an worker from the records */ public void deleteWorker(Integer WorkerID){ Session session = factory.openSession(); Transaction tx = null; try{ tx = session.beginTransaction(); Worker worker = (Worker)session.get(Worker.class, WorkerID); session.delete(worker); tx.commit(); }catch (HibernateException e) { if (tx!=null) tx.rollback(); e.printStackTrace(); }finally { session.close(); } } }
OUTPUT
When you execute the above example you will get the following output in console :
Hibernate: insert into Worker (first_name, last_name, salary) values (?, ?, ?) Hibernate: insert into Worker (first_name, last_name, salary) values (?, ?, ?) Hibernate: insert into Worker (first_name, last_name, salary) values (?, ?, ?) Hibernate: select worker0_.id as id0_, worker0_.first_name as first2_0_, worker0_.last_name as last3_0_, worker0_.salary as salary0_ from Worker worker0_ First Name: Ram Last Name: Prasad Salary: 1000 First Name: Rahul Last Name: Das Salary: 5000 First Name: Steven Last Name: Abraham Salary: 10000 Hibernate: select worker0_.id as id0_0_, worker0_.first_name as first2_0_0_, worker0_.last_name as last3_0_0_, worker0_.salary as salary0_0_ from Worker worker0_ where worker0_.id=? Hibernate: update Worker set first_name=?, last_name=?, salary=? where id=? Hibernate: select worker0_.id as id0_0_, worker0_.first_name as first2_0_0_, worker0_.last_name as last3_0_0_, worker0_.salary as salary0_0_ from Worker worker0_ where worker0_.id=? Hibernate: delete from Worker where id=? Hibernate: select worker0_.id as id0_, worker0_.first_name as first2_0_, worker0_.last_name as last3_0_, worker0_.salary as salary0_ from Worker worker0_ First Name: Ram Last Name: Prasad Salary: 5000 First Name: Steven Last Name: Abraham Salary: 10000