Unknown entity: org.hibernate.engine.transaction.internal.TransactionImpl

Question

I am using hibernate5. I have placed my hibernate.cfg.xml file in config folder of same package.The following error is observed when I tried to run the code

org.hibernate.MappingException: Unknown entity: org.hibernate.engine.transaction.internal.TransactionImpl
    at org.hibernate.metamodel.internal.MetamodelImpl.entityPersister(MetamodelImpl.java:670)
    at org.hibernate.internal.SessionImpl.getEntityPersister(SessionImpl.java:1692)
    at org.hibernate.event.internal.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:122)
    at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:192)
    at org.hibernate.event.internal.DefaultSaveEventListener.saveWithGeneratedOrRequestedId(DefaultSaveEventListener.java:38)
    at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:177)
    at org.hibernate.event.internal.DefaultSaveEventListener.performSaveOrUpdate(DefaultSaveEventListener.java:32)
    at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:73)
    at org.hibernate.internal.SessionImpl.fireSave(SessionImpl.java:709)
    at org.hibernate.internal.SessionImpl.save(SessionImpl.java:701)
    at org.hibernate.internal.SessionImpl.save(SessionImpl.java:696)
    at hibernate.CustomerDAO.addCustomer(CustomerDAO.java:13)
    at hibernate.ClientDemo.main(ClientDemo.java:19)

this is my Hibernate.util file

package hibernate;

import org.hibernate.SessionFactory;
import org.hibernate.boot.Metadata;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;

public class HibernateUtil {

    private static final SessionFactory sessionFactory = buildSessionFactory();

    private static SessionFactory buildSessionFactory() {
        try {
            SessionFactory sessionFactory = new Configuration().configure("/config/hibernate.cfg.xml").buildSessionFactory();
            return sessionFactory;
        } 
        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;
    }

}

This is my hibernate.cfg.xml file

<?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="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</property>
        <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/myschema</property>
        <property name="hibernate.connection.username">root</property>
        <property name="hibernate.connection.password">aar@123</property>
        <property name="show_sql">true</property>
        <mapping class="hibernate.Customer" />
    </session-factory>
</hibernate-configuration>

Can anyone suggest me the solution ?

Answer 1

The mistake was in my CustomerDAO.java class Instead of passing entity object in session.save() I passed transaction object.The error is resolved now.