Creating database
connection.
මෙහිදී database
configurations කල හැකි ආකාර 2කි.
01. Using
Java class.
02. Using
XML file.
01.
Using Java class.
@Configuration
@ComponentScan (basePackages={"com.lhu.backend.dto"})
@EnableTransactionManagement
public class
HibernateConfig{}
In hibernate we required a data source, session factory
which provide some sessions and using those sessions we can create and execute
queries and those executes quarries should be managed within transaction.
@Configuration – telling about we are
creating some configuration class and that been should be handle by spring.
@ComponentScan(basePackages={"com.lhu.backend.dto"})
- Telling where
the entity class are located that hibernate required.
@EnableTransactionManagement – telling to spring to enable the transaction management.
we are not going to handle it.
In here needs to create 3 beans
- @Bean
1.
DataSourse
– providing connection information of the data base.
2.
SessionFactory
– Configure the application to use hibernate and then provide a session object.
It is used the data source and it provides a session for particular user. Using
this session user create queries and then it will execute within the
transaction.
3.
HibernateTransactionManagement -to manage the hibernate transactions
Needs to match with hibernate version
which you are using.(if you are using version 5) If org.springframework.orm.hibernate4.HibernateTransactionManager
this
should be change as
org.springframework.orm.hibernate5.HibernateTransactionManager
import
org.springframework.orm.hibernate5.HibernateTransactionManager;
import
org.springframework.orm.hibernate5.LocalSessionFactoryBuilder;
All the entity class (used to
transfer the data to the relational database) which related to the database
should be annotated with @Entity. Class name (entity name) should be same name
with database name. Unless you want to change it.
import java.util.Properties;
import javax.sql.DataSource;
import org.apache.commons.dbcp2.BasicDataSource;
import org.hibernate.SessionFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.orm.hibernate5.HibernateTransactionManager;
import org.springframework.orm.hibernate5.LocalSessionFactoryBuilder;
import org.springframework.transaction.annotation.EnableTransactionManagement;
@Configuration
@ComponentScan(basePackages={"com.lhu.backend.dto"})
@EnableTransactionManagement
Public class HibernateConfig {
// Change the below based on the DBMS you choose
Privatefinalstatic String DATABASE_URL = "jdbc:mysql://localhost:3306/onlineshopping";
Privatefinalstatic String DATABASE_DRIVER = "com.mysql.jdbc.Driver";
Privatefinalstatic String DATABASE_DIALECT = "org.hibernate.dialect.MySQLDialect";
Privatefinalstatic String DATABASE_USERNAME = "root";
Privatefinalstatic String DATABASE_PASSWORD = "root";
// dataSource bean will be available
@Bean("dataSource")
Public DataSource getDataSource() {
BasicDataSourcedataSource = newBasicDataSource();
// Providing the database connection information
dataSource.setDriverClassName(DATABASE_DRIVER);
dataSource.setUrl(DATABASE_URL);
dataSource.setUsername(DATABASE_USERNAME);
dataSource.setPassword(DATABASE_PASSWORD);
return dataSource;
}
// sessionFactory bean will be available
@Bean
Public SessionFactory getSessionFactory(DataSource dataSource) {
LocalSessionFactoryBuilder builder = new LocalSessionFactoryBuilder(dataSource);
builder.addProperties(getHibernateProperties());
builder.scanPackages("com.lhu.backend.dto");
return builder.buildSessionFactory();
}
// All the hibernate properties will be returned in this method
Private Properties getHibernateProperties() {
Properties properties = new Properties();
properties.put("hibernate.dialect", DATABASE_DIALECT);
properties.put("hibernate.show_sql", "true");
properties.put("hibernate.format_sql", "true");
//properties.put("hibernate.hbm2ddl.auto", "create");
return properties;
}
// transactionManager bean
@Bean
Public HibernateTransactionManager getTransactionManager(SessionFactory sessionFactory) {
HibernateTransactionManager transactionManager = new HibernateTransactionManager(sessionFactory);
return transactionManager;
}
}
That connection can be used as
bellows.
import java.util.List;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;
@Repository("cartLineDAO")
@Transactional
Publicclass CartLineDAOImpl implements CartLineDAO {
@Autowired
Private SessionFactory sessionFactory;
@Override
Publicboolean addUpdateRemove(CartLinecartLine) {
try {
sessionFactory.getCurrentSession().persist(cartLine);
sessionFactory.getCurrentSession().update(cartLine);
sessionFactory.getCurrentSession().delete(cartLine);
return true;
}catch(Exception ex) {}
}
@Override
publicCartLine get(int id) {
return sessionFactory.getCurrentSession().get(CartLine.class, Integer.valueOf(id));
}
@Override
Public List<Category> list() {
String selectActiveCategory = "FROM Category WHERE active = :active";
Query query = sessionFactory.getCurrentSession().createQuery(selectActiveCategory);
query.setParameter("active", true);
return query.getResultList();
}
@Override
Public CartLine getByCartAndProduct(intcartId, intproductId) {
Stringquery = "FROM CartLine WHERE cartId = :cartId AND product.id = :productId";
return sessionFactory.getCurrentSession()
.createQuery(query,CartLine.class)
.setParameter("cartId", cartId)
.setParameter("productId", productId)
.getSingleResult();
}
@Override
Public List<CartLine> listAvailable(int cartId) {
String query = "FROM CartLine WHERE cartId = :cartId AND available = :available";
return sessionFactory.getCurrentSession()
.createQuery(query, CartLine.class)
.setParameter("cartId", cartId)
.setParameter("available", true)
.getResultList();
}
@Override
Public List<Product>
getLatestActiveProducts(
int count) {
return sessionFactory
.getCurrentSession()
.createQuery("FROM Product WHERE active = :active ORDER BY id", Product.class)
.setParameter("active", true)
.setFirstResult(0)
.setMaxResults(count)
.getResultList();
}
}
Other way to do it.
01. Using XML file.
Do all configurations in a xml
file.
Adding database configuration file as XML file
Right click on the project – new – other – search hibernate and select
Hibernate Configuration File(cfg.xml) – next – then file can be change or not
(if it is change that name should be manually provided in the place where hibernate configuration
file name should be provided. It also explain bellow) – next provide related
information and finish.
ඒසේ සදෙන XML file එකේ default name එක hibernate.cfg.xml වේ.නමුත් අප custom file name එකක් යොදාගන්නේ නම් (eg: hibernateConfigure.cfg.xml ) ඒ නම පහත පරිදි code එක තුලදී ලබදිය යුතුය.
Configuration con = new Configuration ().configure(“hibernateConfigure.cfg.xml
“);
නමුත් default name එක බාවිතා වන්නේ නම් code එක තුලදී ඒ නම
සදහන් කිරීම අවශ්යම නොවේ.
Configuration con = new Configuration().configure();
Hibernate.cfg.xml FILE
////////////////////////////////////////////////////////////////////////////////////////
<?xmlversion="1.0"encoding="UTF-8"?>
<!DOCTYPEhibernate-configurationPUBLIC
"-//Hibernate/Hibernate
Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<propertyname="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<propertyname="hibernate.connection.password">root</property>
<propertyname="hibernate.connection.url">
jdbc:mysql://localhost:3306/JerseyRestCompay
</property>
<propertyname="hibernate.connection.username">root</property>
<propertyname="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<propertyname="hbm2ddl.auto">update</property>
<propertyname="show_sql">true</property>
</session-factory>
</hibernate-configuration>
////////////////////////////////////////////////////////////////////////////////////////
<property name="hbm2ddl.auto">update</property>
This tells whether data base table should be newly created or updates.
Java class කලින් හදාගෙන
ඊටපස්සේ ඒ class වලින් database එකේ table හැදෙන්න
ඕනෙනම් පලවෙනි පර project එක run කරද්දී create ලෙස තිබියවේ.මෙවිට database එකේ අලුතෙන් table සදගනී.උදාහරණයක් ලෙස
Employee entity class එක අපි java වල හදල එකකට employee කියලා table
එකක් database හදාගන්න ඕනෙනම් create ලෙස තිබ්බම
අලුතෙන් එකක් සාදාගනී.employee කියලා table එකක්
තිබ්බොත් එක delete කරලා යේ අලුතෙන් එකක් සදයි.නමුත් update ලෙස තිබ්බම වෙන්නේ database එකේemployee කියලා table එකක් තියනවනම්
එක update වෙන එකියි.එහෙමtable එකක් නැත්තම්
එක error එකක් ලෙස එනවා.
<property name="show_sql">true</property>
අපි hibernate වලදී බාවිතා කරන්නේ HQL හෙවත් hibernate query language වේ.නමුත් hibernateවලදී එය SQL වලට convert කරවාගෙන තමා database hit වීමවෙන්නේ.එහිදී අපිට අප
දෙන HQL එකට අදාළ SQL එක බලාගන්න ඕනෙනම්, ඉහත පරිදී (Hibernate.cfg.xml
තුල)දෙන්න ඔනී.මෙවිට HQL වලට අදාළSQL query console එකේ බලාගත හැක.
package com.lahiru.daoImpl;
import com.lahiru.dao.HotelDao;
import com.lahiru.dto.City;
import com.lahiru.dto.Hotels;
import java.nio.channels.SeekableByteChannel;
import java.util.ArrayList;
import java.util.List;
import org.hibernate.Query;
import org.hibernate.SQLQuery;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
import org.springframework.stereotype.Repository;
@Repository("hotelDaoImpl")
public class HotelDaoImpl implements HotelDao{
public static Session sessionBulder(){
Configuration con = new Configuration().configure().addAnnotatedClass(City.class).addAnnotatedClass(Hotels.class);
ServiceRegistry reg = new ServiceRegistryBuilder().applySettings(con.getProperties()).buildServiceRegistry();
SessionFactory sf = con.buildSessionFactory(reg);
Session session = sf.openSession();
return session;
}
@Override
public List getCityNames(){
Session session = HotelDaoImpl.sessionBulder();
SQLQuery Squery = session.createSQLQuery("select * from city");
List<Object[]> nm = (List<Object[]>) Squery.list();
List<City> city = new ArrayList<City>();
City c ;
for (Object[] ct: nm){
c = newCity();
c.setCity_code((Integer)ct[0]);
c.setCity_name((String)ct[1]);
city.add(c);
}
return city;
}
@Override
public List<City> cityInfo(){
Session session = HotelDaoImpl.sessionBulder();
Query query = session.createQuery("from City");
List list = query.list();
return list;
}
@Override
public List<City> getAllHotels(){
Session session = HotelDaoImpl.sessionBulder();
Query query = session.createQuery("from Hotels");
List list = query.list();
return list;
}
@Override
public List<City> getSelectedCityHotels(int city_code){
Session session = HotelDaoImpl.sessionBulder();
Query query = session.createQuery("from Hotels where city_code = ?");
query.setParameter(0, city_code);
List list = query.list();
return list;
}
@Override
public Hotels getOneHotelInfo(int hotel_id){
Session session = HotelDaoImpl.sessionBulder();
Query query = session.createQuery("from Hotels where hotel_id = ?");
query.setParameter(0, hotel_id);
Hotels ht = (Hotels) query.uniqueResult();
return ht;
}
@Override
public String insertHotelInfo(String name, String address, int city_code,String Image_name){
Session session = HotelDaoImpl.sessionBulder();
Hotels ht = new Hotels();
ht.setHotel_address(address);
ht.setHotel_name(name);
ht.setCity_code(city_code);
ht.setImage_name(Image_name);
Transaction tx = session.beginTransaction();
session.save(ht);
session.getTransaction().commit();
session.close();
return "Successfully Added";
}
@Override
public List<City> getSearchedHotels(String q,int b) {
Session session = HotelDaoImpl.sessionBulder();
Query query=null;
if(b==0&& q==null){
query = session.createQuery("from Hotels");
}
elseif(b==0){
query = session.createQuery("from Hotels where hotel_name like ?");
query.setParameter(0, "%"+q+"%");
}
elseif(q==null){
query = session.createQuery("from Hotels where city_code = ?");
query.setParameter(0, b);
}
else{
query = session.createQuery("from Hotels where city_code = ? and hotel_name like ?");
query.setParameter(0, b);
query.setParameter(1, "%"+q+"%");
}
Listlist = query.list();
return list;
}
}
Comments
Post a Comment