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MySQL table not mapped by Hibernate 5+

I'm trying to learn Hibernate using MySQL built-in database named world. It has three tables called city, country and countrylanguage. What I'm trying to do is execute SQL statement SELECT * FROM world.city;. When I run my project I'm getting error
org.hibernate.hql.internal.ast.QuerySyntaxException: City is not mapped [from City]
I'm using IntelliJ IDEA and Hibernate 5.2.8.
I created mapping xml file like this:
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping package="pl.hibernatePackage">
<class name="City" table="city">
<id name="id" column="ID" type="int">
<generator class="native"/>
</id>
<property name="name" column="Name" type="string"/>
<property name="countryCode" column="CountryCode" type="string"/>
<property name="district" column="District" type="string"/>
<property name="population" column="Population" type="int"/>
</class>
</hibernate-mapping>
City.java is presented below:
public class City
{
private Integer id;
private String name;
private String countryCode;
private String district;
private Integer population;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getCountryCode() {
return countryCode;
}
public void setCountryCode(String countryCode) {
this.countryCode = countryCode;
}
public String getDistrict() {
return district;
}
public void setDistrict(String district) {
this.district = district;
}
public Integer getPopulation() {
return population;
}
public void setPopulation(Integer population) {
this.population = population;
}
}
I'm creating session in HibernateUtil.java
public class HibernateUtil
{
private static final SessionFactory sessionFactory = buildSessionFactory();
private static SessionFactory buildSessionFactory() {
try {
Configuration configuration = new Configuration();
configuration.configure();
StandardServiceRegistryBuilder standardServiceRegistryBuilder = new StandardServiceRegistryBuilder();
standardServiceRegistryBuilder.applySettings(configuration.getProperties());
ServiceRegistry serviceRegistry = standardServiceRegistryBuilder.build();
return configuration.buildSessionFactory(serviceRegistry);
}
catch(Exception e) {
throw new ExceptionInInitializerError(e);
}
}
public static SessionFactory getSessionFactory() {
return sessionFactory;
}
}
Configuration file
<?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.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/world</property>
<property name="hibernate.connection.username">test</property>
<property name="hibernate.connection.password">1234</property>
<property name="connection.pool_size">1</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="current_session_context_class">thread</property>
<property name="show_sql">false</property>
<property name="hbm2ddl.auto">update</property>
<!-- List of XML mapping files -->
<mapping resource="pl/hibernatePackage/City.hbm.xml"/>
</session-factory>
</hibernate-configuration>
Main
public class Main
{
public static void main(String[] args)
{
Session session = HibernateUtil.getSessionFactory().getCurrentSession();
session.beginTransaction();
List<City> cities = session.createQuery("from City").list();
for(City c : cities) {
System.out.println(c.getId() + "\t" + c.getName() + "\t" + c.getCountryCode() + "\t" + c.getDistrict() +
"\t" + c.getPopulation());
}
session.getTransaction().commit();
HibernateUtil.getSessionFactory().close();
}
}
EDIT Full error list
EDIT 2
javac result

I have done some testing and i made it work by using the fully qualified class name:
session.createQuery("from pl.hibernatePackage.City")
Now this is only a workaround without touching your config..
After digging deeper i found out that since hibernate version 5.x, there is a different strategy for building the sessionFactory.
I made your example work by implementing sessionFactory as follows:
StandardServiceRegistry standardRegistry = new StandardServiceRegistryBuilder()
.configure()
.build();
Metadata metadata = new MetadataSources( standardRegistry )
.getMetadataBuilder()
.build();
return configuration.buildSessionFactory(serviceRegistry);
This is explained with example here: jboss documentation (point 2.4)

Thanks to Maciej's answer and help of other guys I managed to get my example to work by modifying code and cleaning it up a little. I also found out that mapping DB with xml file is outdated so I modifiied properly CityEntity class. Final code:
Main.java
import org.hibernate.Session;
import java.util.List;
public class Main
{
public static void main(String[] args)
{
Session session = HibernateUtil.getSession();
session.beginTransaction();
List<CityEntity> cities = session.createQuery("from CityEntity").list();
for(CityEntity c : cities)
{
System.out.println(c.getId() + "\t" + c.getName() + "\t" + c.getCountryCode() + "\t" + c.getDistrict() +
"\t" + c.getPopulation());
}
session.getTransaction().commit();
HibernateUtil.close();
}
}
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>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/world</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password">1234</property>
<property name="connection.pool_size">1</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="show_sql">true</property>
<property name="hbm2ddl.auto">update</property>
<!-- List of mapped classes -->
<mapping class="CityEntity"/>
</session-factory>
</hibernate-configuration>
HibernateUtil.java
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
public class HibernateUtil
{
private static final SessionFactory sessionFactory = buildSessionFactory();
private static SessionFactory buildSessionFactory() {
try {
Configuration configuration = new Configuration();
configuration.configure();
StandardServiceRegistry standardRegistry = new StandardServiceRegistryBuilder()
.configure()
.build();
return configuration.buildSessionFactory(standardRegistry);
}
catch(Exception e) {
throw new ExceptionInInitializerError(e);
}
}
public static Session getSession()
{
return sessionFactory.openSession();
}
public static void close()
{
sessionFactory.close();
}
}
CityEntity.java
import javax.persistence.*;
#Entity
#Table(name = "city", schema = "world")
public class CityEntity
{
private int id;
private String name;
private String countryCode;
private String district;
private int population;
#Basic
#Column(name = "CountryCode")
public String getCountryCode() {
return countryCode;
}
public void setCountryCode(String countryCode) {
this.countryCode = countryCode;
}
#Id
#Column(name = "ID")
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
#Basic
#Column(name = "Name")
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
#Basic
#Column(name = "District")
public String getDistrict() {
return district;
}
public void setDistrict(String district) {
this.district = district;
}
#Basic
#Column(name = "Population")
public int getPopulation() {
return population;
}
public void setPopulation(int population) {
this.population = population;
}
}

Hibernate 5.0.2 with Sqlite -- cannot get it working due to errors

While investigating Hibernate / JPA / ORM I found a HibernateHelloWorld Java application from the net.
Via Maven I use these libs:
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-core</artifactId>
<version>5.0.2.Final</version>
</dependency>
<dependency>
<groupId>org.xerial</groupId>
<artifactId>sqlite-jdbc</artifactId>
<version>3.15.0</version>
</dependency>
[1] When running the app, my first issue was that no table could be created. OK, I created the table.
[2] Second issue was that the commit could not be done.
[3] Third issue is that the database keeps on being locked.
The hibernate config file is:
<?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="show_sql">true</property>
<property name="format_sql">true</property>
<property name="dialect">org.hibernate.dialect.SQLiteDialect</property>
<property name="connection.driver_class">org.sqlite.JDBC</property>
<property name="connection.url">jdbc:sqlite:mydb.db</property>
<property name="connection.username"></property>
<property name="connection.password"></property>
<property name="hibernate.hbm2ddl.auto">update</property>
<mapping class="nl.deholtmans.HibernateHelloWorld.Contact"/>
</session-factory>
</hibernate-configuration>
The POJO with annotations is:
#Entity
#Table(name = "contact")
public class Contact {
private Integer id;
private String name;
private String email;
public Contact() {
}
public Contact(Integer id, String name, String email) {
this.id = id;
this.name = name;
this.email = email;
}
#Id
public Integer getId() {
return this.id;
}
// etc.
The simple HibernateHelloWorld app is this:
public class App {
private static SessionFactory sessionFactory = null;
private static SessionFactory configureSessionFactory() throws HibernateException {
sessionFactory = new Configuration()
.configure()
.buildSessionFactory();
return sessionFactory;
}
public static void main(String[] args) {
configureSessionFactory();
Session session = null;
Transaction tx=null;
try {
session = sessionFactory.openSession();
tx = session.beginTransaction();
Contact myContact = new Contact(202, "My Name", "my_email#email.com");
Contact yourContact = new Contact(203, "Your Name", "your_email#email.com");
session.save(myContact);
session.save(yourContact);
session.flush();
tx.commit();
List<Contact> contactList = session.createQuery("from Contact").list();
for (Contact contact : contactList) {
System.out.println("Id: " + contact.getId() + " | Name:" + contact.getName() + " | Email:" + contact.getEmail());
}
} catch (Exception ex) {
ex.printStackTrace();
tx.rollback();
} finally{
if(session != null) {
session.close();
}
}
}
}

To get Hibernate working in combination with Sqlite, I finally found:
[1] I used a newer version of hibernate-core: 5.1.2.
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-core</artifactId>
<version>5.1.2.Final</version>
</dependency>
[2] I used the following dialect and identity files:
https://github.com/gwenn/sqlite-dialect/tree/master/src/main/java/org/hibernate/dialect
[3] And I added column names to the POJO. I guess this was not the main break through. So, for example:
#Entity
#Table(name = "contact")
public class Contact {
#Column(name = "id")
private Integer id;
#Column(name = "name")
private String name;
#Column(name = "email")
private String email;
public Contact() {
}
// etc.
==> I hope the creators of Hibernate can add a simple and good tutorial on integrating Hibernate with Sqlite.

your database seems to be locked. I found this topic:
Getting [SQLITE_BUSY] database file is locked with select statements
Hope this helps.

NullPointerException on Hibernate new Configuration();

This is my first time trying out Hibernate with Eclipse and the following are the things I did:
Created a Java Bean called Student.java which is as follows:
package com.jwt.hibernate;
public class Student {
private long id;
private String name;
private String degree;
private String roll;
private String phone;
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getDegree() {
return degree;
}
public void setDegree(String degree) {
this.degree = degree;
}
public String getRoll() {
return roll;
}
public void setRoll(String roll) {
this.roll = roll;
}
public String getPhone() {
return phone;
}
public void setPhone(String phone) {
this.phone = phone;
}
}
Created a mapping file, Student.hbm.xml as follows:
<hibernate-mapping>
<class name="com.jwt.hibernate.Student" table="student">
<id column="ID" name="id" type="long" />
<property column="name" name="name" type="string" />
<property column="degree" name="degree" type="string" />
<property column="roll" name="roll" type="string" />
<property column="phone" name="phone" type="string" />
</class>
</hibernate-mapping>
3. Created the hibernate configuration file, hibernate.cfg.xml as follows:
<?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.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/hibernatetutorial</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password">root</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="show_sql">true</property>
<property name="format_sql">true</property>
<property name="hbm2ddl.auto">create </property>
<mapping resource="com/jwt/hibernate/Student.hbm.xml" />
</session-factory>
</hibernate-configuration>
Created the class SimpleTest.java which is as follows:
package com.jwt.hibernate;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
public class SimpleTest {
public static void main(String[] args) {
Configuration cfg = new Configuration();
cfg.configure("hibernate.cfg.xml");
SessionFactory factory = cfg.buildSessionFactory();
Session session = factory.openSession();
Student student = new Student();
student.setName("Mukesh");
student.setRoll("101");
student.setPhone("8888");
student.setDegree("B.E");
Transaction tx = session.beginTransaction();
session.save(student);
System.out.println("Object saved successfully.....!!");
tx.commit();
session.close();
factory.close();
}
}
Now, when I try to run SimpleTest, I get the following error:
**INFO: HHH000412: Hibernate Core {4.3.7.Final}
Exception in thread "main" java.lang.ExceptionInInitializerError
at org.hibernate.cfg.Configuration.reset(Configuration.java:326)
at org.hibernate.cfg.Configuration.<init>(Configuration.java:291)
at org.hibernate.cfg.Configuration.<init>(Configuration.java:295)
at com.jwt.hibernate.SimpleTest.main(SimpleTest.java:11)
Caused by: java.lang.NullPointerException
at org.hibernate.internal.util.ConfigHelper.getResourceAsStream(ConfigHelper.java:170)
at org.hibernate.cfg.Environment.<clinit>(Environment.java:221)
... 4 more**
I double checked and made sure that all the configuration and jar files were added to the classpath. So that is not the problem. I would really appreciate some insights as to what may have caused this problem and inturn, how to solve it.
Thanks in advance!

I would recommend updating to later version of SLF4J.
Or
Your Hibernate.cfg.xml is not on classpath. What folder is it in?
Edit :
Caused by: java.lang.NullPointerException
at org.hibernate.internal.util.ConfigHelper.getResourceAsStream(ConfigHelper.java:170)
This is actual exception in your code, If your Hibernate.cfg.xml is loaded then check for SELF4J version, Don't use user library to take your jar files, put all libraries in your lib folder and then configure those in class path.

You may find a Java Configuration of Hibernate to be more friendly. Here is an example of one that I did (Note: there are Spring annotations like #Autowired and #PostConstruct in this class so don't get confused):
public class HibernateConfigBean {
private static final Logger logger = Logger.getLogger(HibernateConfigBean.class);
#Autowired private Environment environment;
private SessionFactory sessionFactory;
private Configuration configuration;
#PostConstruct
private void init(){
configuration = new Configuration();
configuration.setProperty("hibernate.dialect", environment.getProperty("hibernate.dialect"));
configuration.setProperty("hibernate.connection.driver_class", environment.getProperty("hibernate.connection.driver_class"));
configuration.setProperty("hibernate.connection.url", environment.getProperty("hibernate.connection.url"));
configuration.setProperty("hibernate.connection.username", environment.getProperty("db_username"));
configuration.setProperty("hibernate.connection.password", environment.getProperty("db_password"));
//Add additional Annotated Classes here
configuration.addAnnotatedClass(UserEntity.class);
StandardServiceRegistryBuilder builder = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties());
sessionFactory = configuration.buildSessionFactory(builder.build());
}
public SessionFactory getSessionFactory(){
return sessionFactory;
}
//This should be visible outside of the package as it's only used by the GenerateDbSchema class
void generateSchema() throws Exception {
try{
new SchemaExport(configuration).create(false, true);
} catch (RuntimeException re){
throw new Exception(re);
}
}
}
Then I just put my values into a properties file :-)

At a complete loss: mapping a simple entity via Hibernate

I can't figure out why an object will not map via Annotations. No matter what I try, I always receive this error:
org.hibernate.MappingException: Unknown entity: com.hibernate.practice.Car
I was loosely following the tutorial here but can't seem to get anything working. I've tried to strip the object down to its bare bones (thinking that I was making an error in the code somewhere), but again, even with just an ID, and a name Column, I still fail to get this working.
My hibernate.cfg is from the Netbeans Hibernate tutorial.
<?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.url">jdbc:mysql://localhost:3306/practicedb?zeroDateTimeBehavior=convertToNull</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password">pass</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.show_sql">true</property>
<property name="hibernate.hbm2ddl.auto">create</property>
<property name="hibernate.current_session_context_class">thread</property>
</session-factory>
</hibernate-configuration>
Also, per the instructions, I've added the HibernateUtil.java class.
public class HibernateUtil {
private static final SessionFactory sessionFactory;
static {
try {
// Create the SessionFactory from standard (hibernate.cfg.xml)
// config file.
sessionFactory = new AnnotationConfiguration().configure().addPackage("com.hibernate.practice").buildSessionFactory();
} catch (Throwable ex) {
// Log the exception.
System.err.println("Initial SessionFactory creation failed." + ex);
throw new ExceptionInInitializerError(ex);
}
}
public static SessionFactory getSessionFactory() {
return sessionFactory;
}
}
I set up a simple class. It's a Car with an ID and a Name.
#Entity
public class Car {
#Id
#GeneratedValue
#GenericGenerator(name="increment", strategy="incrememnt")
private long id;
#Column(name="car_name")
private String name;
public Car() {
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
And finally, I'm trying to test this stuff out like this:
#Test
public void testOutHibernate() {
SessionFactory factory = HibernateUtil.getSessionFactory();
Session session = factory.openSession();
Car car = new Car();
car.setName("red one");
session.save(car);
try {
Transaction t = session.beginTransaction();
session.save(car);
t.commit();
}
finally {
session.close();
}
session.close();
}
Without fail I get the Unknown Entity Exception. Is there something glaringly obvious that I'm missing?

You need to add your annotated class as follows -
sessionFactory = new AnnotationConfiguration()
.addAnnotatedClass(Car.class)
.addPackage("com.hibernate.practice")
.configure()
.buildSessionFactory();
You can find a discussion regarding the addPackage() method here - https://forum.hibernate.org/viewtopic.php?f=1&t=980723.

Exception in Hibernate program in eclipse

In my hibernate programme I am getting the following exception:
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.MappingException: An AnnotationConfiguration instance is required to use
My Hibernate.cfg.config file is
<?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">1234</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/mayank</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="show-sql">true></property>
<property name="hbm2ddl.auto">update</property>
<mapping class="one.Student"/>
</session-factory>
</hibernate-configuration>
The Student file is
package one;
import javax.persistence.Entity;
import javax.persistence.Id;
#Entity
public class Student
{
#Id
private Long id;
private int roll;
private String name;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public int getRoll() {
return roll;
}
public void setRoll(int roll) {
this.roll = roll;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Student(Long id, int roll, String name) {
super();
this.id = id;
this.roll = roll;
this.name = name;
}
public Student() {
// TODO Auto-generated constructor stub
}
}
What does the Exception mean and what am I doing wrong?

In place of Configuration cfg = new Configuration();
we need to use AnnotationConfiguration
cfg = new AnnotationConfiguration();
For XML File: Configuration
For Annotation: AnnotationConfiguration

In my case I downloaded dtd file locally on my machine under path(D:/Praful_WorkSpace/firstHibernate/src/hibernate-configuration-3.0.dtd) and then I mentioned that path in the xml file declaration. I followed same thing for both the xml files.
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"file:///D:/Praful_WorkSpace/firstHibernate/src/hibernate-configuration-3.0.dtd">

(1)Add the dependency in Maven's pom.xml
<dependency>
<groupId>hibernate-annotations</groupId>
<artifactId>hibernate-annotations</artifactId>
<version>3.3.0.GA</version>
</dependency>
(2)Use AnnotationConfiguration to build session factory
Normal Hibernate XML file mapping is using Configuration()
return new Configuration().configure().buildSessionFactory();
For Hibernate annotation, you have to change it to AnnotationConfiguration
return new AnnotationConfiguration().configure().buildSessionFactory();