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Hibernate says database.table doesn't exist

The Situation
Ok, so I am learning Hibernate(from 2 days so pardon any blunder), I am using mysql database and just trying tocreate a table Employee and make an entry in database(A demonstration).
Here are the codes
POJO:
package com.sopra.pojo;
import javax.persistence.*;
#Entity
#Table(name = "EMPLOYEE")
public class Employee {
#Id
private int Id;
private String firstName;
private String lastName;
private int salary;
public int getId() {
return Id;
}
public void setId(int id) {
Id = id;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public int getSalary() {
return salary;
}
public void setSalary(int salary) {
this.salary = salary;
}
}
hibernate.cfg.xml which is in src
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.org/dtd/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://localhost:3306/test</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password">password</property>
<property name="hibernate.connection.pool_size">1</property>
<property name="hibernate.current_session_context_class">thread</property>
<property name="hibernate.show_sql">true</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name = "hibernate.hbm2ddl.auto">create</property>
<mapping class="com.sopra.pojo.Employee" />
</session-factory>
</hibernate-configuration>
EmployeeDBManager.java
package com.sopra.pojo;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
public class EmployeeDBManager {
public static void main(String[] args) {
Employee e = new Employee();
e.setFirstName("Salim");
e.setId(672);
e.setLastName("Shamim");
e.setSalary(266);
SessionFactory sessionFactory = new Configuration().configure().buildSessionFactory();
Session session = sessionFactory.openSession();
Transaction tx = session.beginTransaction();
session.persist(e);
tx.commit();
session.close();
}
}
The Error
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'test.employee' doesn't exist
I've tried
use this in cfg file : <property name="hibernate.hbm2ddl.auto">update</property>
What is interesting is when I manually create the table in mysql using workbench, hibernate does drops it as when i use drop command it says the table doesn't exists.
I can't figure out where the glitch might be(newbie and internet didn't helped).
Please mention any additional details required in comments.
Please help!
Thanks.

I made it worked, I am not sure if it's a proper answer but since it got it working I am posting it as an answer.
I made two changes
I was using hibernate version 5.2.12 so I changed it to 4.2.0 and added jars from two more folders which earlier I hadn't (In summary I have now imported Jars from :optional, provided & required folder in hibernate user library)
I overlooked a url mistake which was
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.org/dtd/hibernate-configuration-3.0.dtd">
In the dtd url I have not added www. It should have been
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">`
So, my mistake.
Anyway, comments regarding improving this answer and why it made it work are deeply appreciated.

add different auto option of hibernate,
Use instead of create , update or create-drop
<property name="hibernate.hbm2ddl.auto">update</property>
or
<property name="hibernate.hbm2ddl.auto">create-drop</property>
You can read more about it here

Exception in hibernate in JDBC

I am running hibernate program in eclipse and try to connect with database.i added all the required jars.but it is throwing
exceptionorg.hibernate.exception.GenericJDBCException
Here is my code:
Employee.java
public class Employee {
private int id;
private String firstName,lastName;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
}
Employee.hbm.xml
<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.acnovate.Employee" table="emp1000">
<id name="id">
<generator class="assigned"></generator>
</id>
<property name="firstName" column="firstname"></property>
<property name="lastName" column="lastname"></property>
</class>
</hibernate-mapping>
hibernate.cfg.xml
<?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="hbm2ddl.auto">update</property>
<property name="dialect">org.hibernate.dialect.Oracle9Dialect</property>
<property name="hibernate.connection.url">jdbc:oracle:thin:#localhost:1521:orcl</property>
<property name="hibernate.connection.username">system</property>
<property name="hibernate.connection.password">Manager7</property>
<property name="hibernate.connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
<mapping resource="Employee.hbm.xml"/>
</session-factory>
</hibernate-configuration>
StoreData.java
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
public class StoreData {
public static void main(String[] args) {
//creating configuration object
Configuration cfg=new Configuration();
cfg.configure("hibernate.cfg.xml");//populates the data of the configuration file
//creating session factory object
SessionFactory factory=cfg.buildSessionFactory();
//creating session object
Session session=factory.openSession();
//creating transaction object
Transaction t=session.beginTransaction();
Employee e1=new Employee();
e1.setId(115);
e1.setFirstName("sonoo");
e1.setLastName("jaiswal");
session.persist(e1);//persisting the object
t.commit();//transaction is committed
session.close();
System.out.println("successfully saved");
}
}
and i am facing the following exception.
Exception in thread "main" org.hibernate.exception.GenericJDBCException: Cannot open connection
at org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:103)
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:91)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:29)
at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:420)
at org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:144)
at org.hibernate.jdbc.JDBCContext.connection(JDBCContext.java:119)
at org.hibernate.transaction.JDBCTransaction.begin(JDBCTransaction.java:57)
at org.hibernate.impl.SessionImpl.beginTransaction(SessionImpl.java:1326)
at com.acnovate.StoreData.main(StoreData.java:22)
Caused by: java.sql.SQLException: Listener refused the connection with the following error:
ORA-12505, TNS:listener does not currently know of SID given in connect descriptor
The Connection descriptor used by the client was:
localhost:1521:orcl
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:112)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:261)
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:387)
at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:414)
at oracle.jdbc.driver.T4CConnection.<init>(T4CConnection.java:165)
at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:35)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:801)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at org.hibernate.connection.DriverManagerConnectionProvider.getConnection(DriverManagerConnectionProvider.java:110)
at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:417)
... 5 more
I checked my code but didn't find any issue.please help me to getting out of this errors.
Thanks in Advance.

You need to check this
jdbc:oracle:thin:#localhost:1521:orcl
Oracle doesn't recognize orcl SID.

Hibernate 5: sessionFactory is null

Im getting a null value for sessionFactory variable at this line:
sessionFactory = new MetadataSources( registry ).buildMetadata().buildSessionFactory();
This is the whole class:
import javax.imageio.spi.ServiceRegistry;
import javax.transaction.Transaction;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
import ch.makery.model.Employee;
public class HelloWorld {
protected void setUp() throws Exception {
}
public static void main(String[] args) {
SessionFactory sessionFactory = null;
// A SessionFactory is set up once for an application!
final StandardServiceRegistry registry = new StandardServiceRegistryBuilder()
.configure() // configures settings from hibernate.cfg.xml
.build();
try {
sessionFactory = new MetadataSources( registry ).buildMetadata().buildSessionFactory();
}
catch (Exception e) {
// The registry would be destroyed by the SessionFactory, but we had trouble building the SessionFactory
// so destroy it manually.
StandardServiceRegistryBuilder.destroy( registry );
}
Session session = sessionFactory.openSession();
//employee = new Employee();
session.beginTransaction();
session.save(new Employee());
session.getTransaction().commit();
session.close();
}
}
This is my Hibernate related files:
<?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.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.password">manolete</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/employee</property>
<property name="hibernate.connection.username">root</property>
<property name="cache.provider_class">org.hibernate.cache.internal.NoCacheProvider</property>
<property name="hbm2ddl.auto">create</property>
<mapping resource="src/ch/makery/model/Employee.hbm.xml" />
</session-factory>
</hibernate-configuration>
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- Generated 14-dic-2015 21:00:04 by Hibernate Tools 3.4.0.CR1 -->
<hibernate-mapping>
<class name="ch.makery.model.Employee" table="EMPLOYEE">
<id name="id" type="int">
<column name="ID" />
<generator class="assigned" />
</id>
<property name="firstName" type="java.lang.String">
<column name="FIRSTNAME" />
</property>
<property name="lastName" type="java.lang.String">
<column name="LASTNAME" />
</property>
</class>
</hibernate-mapping>
package ch.makery.model;
public class Employee {
private int id;
private String firstName,lastName;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
}
Im not using Spring since Im just creating a desktop application.

The method buildSessionFactory is deprecated from the hibernate 4 release and it is replaced with the new API. If you are using the hibernate 4.3.0 and above try to write the configuration like this:
Configuration configuration = new Configuration().configure();
configuration.configure("your_path_hibernate_.cfg.xml");
StandardServiceRegistryBuilder ssrb = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties());
sessionFactory = configuration.buildSessionFactory(ssrb.build());

When I updated my Hibernate code from v4.1.8 to v5.0.6 I too had a problem with my SessionFactory instance being null. By printing the stack trace I was able to figure out that I needed to include the optional c3p0 jars in my build path.
My first suggestion would be to print the stack trace directly from your catch block. The trace will provide a good starting point on your way toward resolution. So your catch block would look like:
catch (Exception e) {
// The registry would be destroyed by the SessionFactory, but we had trouble building the SessionFactory
// so destroy it manually.
StandardServiceRegistryBuilder.destroy( registry );
e.printStackTrace();
}
However, I notice that you don't have a hibernate.dialect property defined in your configuration file. While this property is not mandatory the Hibernate User Guide notes that there may be "some reason" hibernate is not able to determine which dialect you are using. My second suggestion would be to define your database dialect directly in your configuration file with the hibernate.dialect setting.
Since your original configuration file post suggests that you are making use of the MySQL database dialect, try adding in this dialect property node to the session-factory node:
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
If you are using MySQL 5.x then use
<property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>
Make sure that the optional c3p0 jars are in your build path.
Best of luck!

private static SessionFactory sessionFactory = createSessionFactory();
private static SessionFactory createSessionFactory() {
if (sessionFactory == null) {
StandardServiceRegistry standardRegistry = new StandardServiceRegistryBuilder() .configure("hibernate.cfg.xml").build();
Metadata metaData = new MetadataSources(standardRegistry).getMetadataBuilder().build();
sessionFactory = metaData.getSessionFactoryBuilder().build();
}
return sessionFactory;
}
public static SessionFactory getSessionFactory() {
return sessionFactory;
}
public static void shutdown() {
sessionFactory.getCurrentSession().close();
}

Exception in thread "main" org.hibernate.exception.GenericJDBCException: Cannot open connection

I am trying to run a simple java project to see the working of hibernate but when i am executing my code (StoreData.java) it gives a hibernate exception, i am using oracle 11g R2 and eclipse galileo , my oracle SID is "orcl" connection name is "mysql" username is "sys" password is "oracle". Here is the code:
Employee.java:
*package com.persist;
public class Employee {
private int id;
private String firstName;
private String lastName;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
}*
employee.hbm.xml :
*<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.persist.Employee" table="Emp">
<id name="id">
<generator class="assigned"></generator>
</id>
<property name="firstName"></property>
<property name="lastName"></property>
</class>
</hibernate-mapping>*
hibernate.cfg.xml :
*<?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="hbm2ddl.auto">update</property>
<property name="dialect">org.hibernate.dialect.Oracle9Dialect</property>
<property name="connection.url">jdbc:oracle:thin:#localhost:1521:orcl</property>
<property name="connection.username">sys</property>
<property name="connectio.password">oracle</property>
<property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
<mapping resource="employee.hbm.xml"/>
</session-factory>
</hibernate-configuration>*
StoreData.java :
*package com.DAO;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import com.persist.Employee;
public class StoreData {
/**
* #param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
Configuration cf = new Configuration();
cf.configure("hibernate.cfg.xml");
SessionFactory factory =cf.buildSessionFactory();
Session session =factory.openSession();
Transaction t =session.beginTransaction();
Employee e = new Employee();
e.setId(1);
e.setFirstName("samar");
e.setLastName("singh");
session.persist(e);
t.commit();
session.close();
System.out.println("successfully saved");
}
}*
console:
*log4j:WARN No appenders could be found for logger (org.hibernate.cfg.Environment).
log4j:WARN Please initialize the log4j system properly.
Exception in thread "main" org.hibernate.exception.GenericJDBCException: Cannot open connection
at org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:103)
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:91)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:29)
at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:420)
at org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:144)
at org.hibernate.jdbc.JDBCContext.connection(JDBCContext.java:119)
at org.hibernate.transaction.JDBCTransaction.begin(JDBCTransaction.java:57)
at org.hibernate.impl.SessionImpl.beginTransaction(SessionImpl.java:1326)
at com.DAO.StoreData.main(StoreData.java:27)
Caused by: java.sql.SQLException: invalid arguments in call
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:112)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:146)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:208)
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:236)
at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:414)
at oracle.jdbc.driver.T4CConnection.<init>(T4CConnection.java:165)
at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:35)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:801)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at org.hibernate.connection.DriverManagerConnectionProvider.getConnection(DriverManagerConnectionProvider.java:110)
at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:417)
... 5 more*
project hierarchy :

Try with below property:
<property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
<property name="connection.url">jdbc:Oracle:thin:#localhost:1521:orcl</property>
<property name="connection.username">sys</property>
<property name="connection.password">oracle</property>
<property name="dialect">org.hibernate.dialect.OracleDialect</property>

Try finding the latest ojdbc jar,old ojdbc14 jar wont work with latest db,I got the same issue i have used ojdbc7 jar problem solved

[Hibernate]Error: entity class not found:

I get tired of this for a long time. I do not know what caused this error. Here are my files:
Uzytkownik.hbm.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="Uzytkownik" table="uzytkownicy">
<id column="id" name="id" type="int"/>
<property column="login" generated="never" lazy="false" name="login" type="string"/>
<property column="haslo" generated="never" lazy="false" name="haslo" type="string"/>
</class>
</hibernate-mapping>
hibernate.cfg.xml:
<?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 name="">
<property name="hibernate.connection.driver_class">org.gjt.mm.mysql.Driver</property>
<property name="hibernate.connection.password">root</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost/sprawozdania</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</property>
<mapping resource="com/vaannila/uzytkownik/Uzytkownik.hbm.xml"/>
</session-factory>
</hibernate-configuration>
I use mysql 5.5.
I get the following error:
Exception in thread "main" java.lang.ExceptionInInitializerError
at com.vaannila.util.HibernateUtil.<clinit>(HibernateUtil.java:14)
at com.vaannila.uzytkownik.Main.saveUzyt(Main.java:22)
at com.vaannila.uzytkownik.Main.main(Main.java:16)
Caused by: org.hibernate.MappingException: entity class not found: Uzytkownik
This are my classes:
main.java
package com.vaannila.uzytkownik;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;
import javax.persistence.Entity;
import com.vaannila.util.HibernateUtil;
public class Main {
/**
* #param args
*/
public static void main(String[] args) {
Main obj = new Main();
String uzytkownikLogin = obj.saveUzyt("Adam", "Malysz");
}
public String saveUzyt(String login, String haslo){
Session session = HibernateUtil.getSessionFactory().openSession();
Transaction transaction = null;
String uzytLog = null;
try {
transaction = session.beginTransaction();
Uzytkownik uzyt = new Uzytkownik();
uzyt.setLogin(login);
uzyt.setHaslo(haslo);
uzytLog = (String) session.save(uzyt);
transaction.commit();
} catch (HibernateException e) {
transaction.rollback();
e.printStackTrace();
} finally {
session.close();
}
return uzytLog;
}
}
Uzytkownik.java:
package com.vaannila.uzytkownik;
// default package
// Generated 2011-07-14 13:39:18 by Hibernate Tools 3.4.0.CR1
/**
* Uzytkownik generated by hbm2java
*/
public class Uzytkownik implements java.io.Serializable {
private int id;
private String login;
private String haslo;
public Uzytkownik() {
}
public Uzytkownik(int id) {
this.id = id;
}
public Uzytkownik(int id, String login, String haslo) {
this.id = id;
this.login = login;
this.haslo = haslo;
}
public int getId() {
return this.id;
}
public void setId(int id) {
this.id = id;
}
public String getLogin() {
return this.login;
}
public void setLogin(String login) {
this.login = login;
}
public String getHaslo() {
return this.haslo;
}
public void setHaslo(String haslo) {
this.haslo = haslo;
}
}
HibernateUtil.java:
package com.vaannila.util;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
public class HibernateUtil {
private static final SessionFactory sessionFactory;
static {
try {
sessionFactory = new Configuration().configure().buildSessionFactory();
} catch (Throwable ex) {
System.err.println("Initial SessionFactory creation failed." + ex);
throw new ExceptionInInitializerError(ex);
}
}
public static SessionFactory getSessionFactory() {
return sessionFactory;
}
}

Maybe your mapping file is not complete but other wise it should be:
<class name="com.vaannila.uzytkownik.Uzytkownik" table="uzytkownicy">
=> need to set fully qualified class name (with package)

I think it makes sense to specify full-qualified entity class name:
<class name="com.vaannila.uzytkownik.Uzytkownik" table="uzytkownicy">

Don't forget to mention your class using as a entity classes in hibernate configeration file using the mapping tag !!
Example:
<session-factory>
//database configeration goes here
<mapping class="org.fbis.models.Form3A"/>
</session-factory>

Stijn Geukens answers right,but I want to point out more information about this question.
There are two reasons I know causing this problem: entity class not found
First, As Stijn Geukens answers, Your Hibernate mapping is not right, the value of name attribute for the tag class should be the Java class with package ahead.
Second, if you have boolean filed in your Java class, this field can't start with is.Otherwise, the hibernate throws an exception getter method is not found... when run by Java Debug mode or Run mode.But when it comes to web project and you run your project as Server Application,the message becomes entity class not found.It made me puzzled for a long time.So do not name your boolean field with is ahead.