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Connect to a database dynamically in hibernate

So I have multiple pluggable databases (PDBs) and I want to connect to any one of them dynamically using Hibernate. How do I achieve such functionality?
To connect to PDB1 (and likewise for other PDBs), I have:
protected void setupPdb1() {
final StandardServiceRegistry registry = new StandardServiceRegistryBuilder()
.configure("hibernate-1.cfg.xml") // configures settings from hibernate.cfg.xml
.build();
try {
sessionFactory1 = new MetadataSources(registry).buildMetadata().buildSessionFactory();
} catch (Exception ex) {
StandardServiceRegistryBuilder.destroy(registry);
throw new RuntimeException(ex);
}
}
My hibernate config file corresponding to PDB1 is as follows:
<?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="connection.url">jdbc:oracle:thin:#//localhost:1521/pdb1.oradev.oraclecorp.com</property>
<property name="connection.username">test</property>
<property name="connection.password">password12</property>
<property name="connection.driver_class">oracle.jdbc.OracleDriver</property>
<property name="dialect">org.hibernate.dialect.Oracle12cDialect</property>
<property name="show_sql">true</property>
<property name="format_sql">true</property>
<property name="hbm2ddl.auto">create</property>
<!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size">1</property>
<property name="current_session_context_class">thread</property>
<mapping class="net.codejava.hibernate.Book" />
</session-factory>
</hibernate-configuration>
The issue with this approach is there is one config file for each PDB. How do I dynamically select the PDB to connect to using Hibernate?

it depends on your strategy, what is the trigger to switch database ?

ERROR: No suitable driver found for jdbc:mysql://localhost:3306/test

I am getting no suitable driver exception. Connection is not created.
package org.srtmun.student.dao.impl;
import javax.transaction.Transaction;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import org.srtmun.student.dao.RegestrationDAO;
import org.srtmun.student.hibernateplugin.HibernatePlug;
import org.srtmun.student.model.Registration;
public class RegistrationDaoImpl implements RegestrationDAO{
public void addStudent(Registration register) {
System.out.println("RegistrationDaoImpl class1");
SessionFactory factory = HibernatePlug.getFactory();
System.out.println("1");
Session session=factory.openSession();
org.hibernate.Transaction tx=session.beginTransaction();
session.save(register);
tx.commit();
session.close();
}
}
<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.connection.password">123</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/test</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<mapping resource="Registration.hbm.xml" />
</session-factory>
</hibernate-configuration>
This is my code and and iam facing the Same issue.

You need to add this property to the hibernate.cfg.xml
<property
name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
And you need to have mysql-connector-java jar at the class path.
Your transaction code is not correct (you don't use rollback, for an example). Refer this for how to properly work with that.

Exception : buildSessionFactory - in Hibernate App

I'm working on an E-Commerce App using Hibernate Framework. But I'm facing a problem during the execution. The test program throws an Exception :
Exception in thread "main" java.lang.ExceptionInInitializerError
at HibernateUtil.buildSessionFactory(HibernateUtil.java:19)
at HibernateUtil.<clinit>(HibernateUtil.java:9)
at Test.main(Test.java:10)
Caused by: java.lang.NullPointerException
at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.processFkSecondPassesInOrder(InFlightMetadataCollectorImpl.java:1708)
at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.processSecondPasses(InFlightMetadataCollectorImpl.java:1617)
at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:278)
at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.build(MetadataBuildingProcess.java:83)
at org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:418)
at org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:87)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:692)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:724)
at HibernateUtil.buildSessionFactory(HibernateUtil.java:14)
... 2 more
My HibernateUtil :
import org.hibernate.*;
import org.hibernate.cfg.*;
public class HibernateUtil {
private static final SessionFactory sessionFactory = buildSessionFactory();
private static SessionFactory buildSessionFactory() {
try {
// Create the SessionFactory from hibernate.cfg.xml
return new Configuration().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;
}
}
Hibernate.cfg.xml
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration SYSTEM
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<!-- local connection properties -->
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/ecom</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password"></property>
<property name="hibernate.connection.pool_size">10</property>
<!-- dialect for MySQL -->
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.current_session_context_class">thread</property>
<property name="hibernate.show_sql">true</property>
<property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>
<property name="cache.use_query_cache">false</property>
<mapping class="Metier.Category"/>
<mapping class="Metier.Customer"/>
<mapping class="Metier.CustomerOrder"/>
<mapping class="Metier.orderedProduct"/>
<mapping class="Metier.orderedProductID"/>
<mapping class="Metier.Product"/>
</session-factory>
</hibernate-configuration>
Please tell me what is the source of the Exception.
Cheers.

how to map classes in hibernate using the class attribute?

I have a problem in my maven project
click the links below to see it
I added this to my hibernate.cfg but didn't work
<mapping package="com.redpass.entities"/>
<mapping class="com.redpass.entities.MyReference"/>
console error
Project Explorer
hibernate.cfg.xml
<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<!-- Database connection settings -->
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://localhost:3306/avocatbd</property>
<property name="connection.username">root</property>
<!-- SQL dialect -->
<property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>
<!-- Echo all executed SQL to stdout -->
<property name="show_sql">true</property>
<!-- <mapping package="com.redpass.entities"/>
<mapping class="com.redpass.entities.MyReference"/> -->
</session-factory>
</hibernate-configuration>

I should add this:
configuration.configure("hibernate.cfg.xml");
return configuration
.buildSessionFactory(new StandardServiceRegistryBuilder()
.applySettings(configuration.getProperties())
.build());
to my HibernateUtil Class to tell that we want to configure using the hibernate.cfg.xml file and map the classes like this:
<mapping class="com.redpass.entities.Partie"/>
<mapping class="com.redpass.entities.Societe"/>

Hibernate does not see data inserted from external application

I am using Hibernate as an ORM for a server daemon.
This code returns no items if the table associated is empty at run time but has an item added outside of hibernate.
public static List<QueueItem> queue()
{
SessionFactory factory = HibernateUtil.getSessionFactory();
Session session = factory.openSession();
session.flush();
session.clear();
#SuppressWarnings("unchecked")
List<QueueItem> topList = session.createQuery("FROM QueueItem i ORDER BY i.id asc").setMaxResults(3).list();
session.close();
return topList;
}
Here is the hibernate config
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration SYSTEM
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://10.10.1.4/lanjukebox_test</property>
<property name="hibernate.connection.username">ussqldev</property>
<property name="hibernate.connection.password">ussqldev</property>
<property name="hibernate.jdbc.batch_size">25</property>
<property name="connection.pool_size">1</property>
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="current_session_context_class">thread</property>
<property name="hibernate.cache.use_second_level_cache">false</property>
<property name="show_sql">false</property>
<property name="hbm2ddl.auto">validate</property>
<!-- List of XML mapping files -->
<mapping resource="usagisoft/lan/jukebox/domain/entities/Song.hbm.xml"/>
<mapping resource="usagisoft/lan/jukebox/domain/entities/Id3.hbm.xml"/>
<mapping resource="usagisoft/lan/jukebox/domain/entities/QueueItem.hbm.xml"/>
<mapping resource="usagisoft/lan/jukebox/domain/entities/Vote.hbm.xml"/>
<mapping resource="usagisoft/lan/jukebox/domain/entities/User.hbm.xml"/>
</session-factory>
</hibernate-configuration>
If I create an object and persist it from within the application it works fine, If there is already data in the table and I insert the data it finds the other objects, the issue arises as soon as the table is empty during run time.
This is a big issue because another application handles the inserting of data for these objects.
I am using hibernate 4.2.7.Final with Java 1.7(jdk1.7.0_45) in eclipse.

You can resolve this problem since
hibernate.cfg.xml
adding this tag:
<property name="hibernate.connection.autocommit">true</property>