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h2 database persists data but resets on application start

I have a basic test for an embedded database that I'm trying to get working for a java project. As it stands now I am able to save rows to the database with my entity repository object, and after the app finishes running, I can connect to the database with intellij and see those rows are still there. But then, if I comment out the save methods and run it again, when I check the database after it finishes, the database is empty.
Entity
package closet.utilities.entities;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;
#Entity
#Table(name = "outfits")
public class Outfit {
#Id
#Column(name = "id")
String id;
#Column(name = "inv_name")
String invName;
#Column(name = "display_name")
String displayName;
#Column(name = "owner")
String owner;
public Outfit() {
}
public Outfit(String id, String invName, String displayName, String owner) {
this.id = id;
this.invName = invName;
this.displayName = displayName;
this.owner = owner;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getInvName() {
return invName;
}
public void setInvName(String invName) {
this.invName = invName;
}
public String getDisplayName() {
return displayName;
}
public void setDisplayName(String displayName) {
this.displayName = displayName;
}
public String getOwner() {
return owner;
}
public void setOwner(String owner) {
this.owner = owner;
}
#Override
public String toString() {
return "Outfit{" +
"id='" + id + '\'' +
", invName='" + invName + '\'' +
", displayName='" + displayName + '\'' +
", owner='" + owner + '\'' +
'}';
}
}
Repository
package closet.utilities.repositories;
import closet.utilities.entities.Outfit;
import javax.persistence.EntityManager;
import java.util.List;
import java.util.Optional;
public class OutfitRepository {
private EntityManager entityManager;
public OutfitRepository(EntityManager entityManager) {
this.entityManager = entityManager;
}
public Optional<Outfit> findById(String id) {
Outfit outfit = entityManager.find(Outfit.class, id);
return outfit != null ? Optional.of(outfit) : Optional.empty();
}
public List<Outfit> findAll() {
return entityManager.createQuery("from Outfit").getResultList();
}
public Optional<Outfit> save(Outfit outfit) {
try {
entityManager.getTransaction().begin();
entityManager.persist(outfit);
entityManager.getTransaction().commit();
return Optional.of(outfit);
} catch (Exception e) {
// TODO logging
e.printStackTrace();
}
return Optional.empty();
}
}
main method
package closet.utilities;
import closet.utilities.entities.Outfit;
import closet.utilities.repositories.OutfitRepository;
import org.hibernate.Session;
import org.hibernate.Transaction;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import java.util.List;
public class Runnable {
public static void main(String[] args) {
// Create our entity manager
EntityManagerFactory entityManagerFactory = Persistence.createEntityManagerFactory("closet");
EntityManager entityManager = entityManagerFactory.createEntityManager();
Outfit outfit = new Outfit("Ramesh", "Fadatare", "rameshfadatare#javaguides.com", "");
Outfit outfit1 = new Outfit("John", "Cena", "john#javaguides.com", "");
OutfitRepository outfitRepository = new OutfitRepository(entityManager);
//outfitRepository.save(outfit);
//outfitRepository.save(outfit1);
List<Outfit> outfits = outfitRepository.findAll();
for (Outfit o : outfits) {
System.out.println(o.getInvName());
}
}
}
persistence.xml
<persistence xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
version="2.0" xmlns="http://java.sun.com/xml/ns/persistence">
<persistence-unit name="closet" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
<class>closet.utilities.entities.Outfit</class>
<properties>
<property name="javax.persistence.jdbc.driver" value="org.h2.Driver" />
<property name="javax.persistence.jdbc.url" value="jdbc:h2:./data/closet" />
<property name="javax.persistence.jdbc.user" value="sa" />
<property name="javax.persistence.jdbc.password" value="" />
<property name="hibernate.dialect" value="org.hibernate.dialect.H2Dialect"/>
<property name="hibernate.hbm2ddl.auto" value="create-drop" />
<property name="show_sql" value="true"/>
<property name="hibernate.temp.use_jdbc_metadata_defaults" value="false"/>
</properties>
</persistence-unit>
</persistence>
hibernate.cfg.xml
<!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>
<!-- JDBC Database connection settings -->
<property name="connection.driver_class">org.h2.Driver</property>
<property name="connection.url">jdbc:h2:./data/closet</property>
<property name="connection.username">sa</property>
<property name="connection.password"></property>
<!-- JDBC connection pool settings ... using built-in test pool -->
<property name="connection.pool_size">1</property>
<!-- Select our SQL dialect -->
<property name="dialect">org.hibernate.dialect.H2Dialect</property>
<!-- Echo the SQL to stdout -->
<property name="show_sql">true</property>
<!-- Set the current session context -->
<property name="current_session_context_class">thread</property>
<!-- Drop and re-create the database schema on startup -->
<property name="hbm2ddl.auto">create-drop</property>
<!-- dbcp connection pool configuration -->
<property name="hibernate.dbcp.initialSize">5</property>
<property name="hibernate.dbcp.maxTotal">20</property>
<property name="hibernate.dbcp.maxIdle">10</property>
<property name="hibernate.dbcp.minIdle">5</property>
<property name="hibernate.dbcp.maxWaitMillis">-1</property>
<mapping class="closet.utilities.entities.Outfit" />
</session-factory>
</hibernate-configuration>
I'm just following this tutorial here as a guide to just figure out how to get it all working. I can't see what I'm doing wrong based on that.

You use:
<property name="hbm2ddl.auto">create-drop</property>
As it is stated in the documentation:
create-drop
Drop the schema and recreate it on SessionFactory startup. Additionally, drop the schema on SessionFactory shutdown.
So, this is expected behaviour.

How can I insert new row in a table using Hibernate?

I'm trying to understand JPA/Hibernate, I'm able to create new database but I don't understand how insert new row in my
database.
This is the code:
import java.io.Serializable;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
#Entity
public class Person implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String name;
private String adress;
private String phoneNumber;
public void setName(String name) {
this.name = name;
}
public void setAdress(String adress) {
this.adress = adress;
}
public void setPhoneNumber(String phoneNumber) {
this.phoneNumber = phoneNumber;
}
public String getName() {
return name;
}
public String getAdress() {
return adress;
}
public String getPhoneNumber() {
return phoneNumber;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
#Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
#Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof Person)) {
return false;
}
Person other = (Person) object;
if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
#Override
public String toString() {
return "entinty.Person[ id=" + id + " ]";
}
}
The class that create the database is:
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
public class Main {
public static void main(String args[]) {
Person p = new Person();
p.setName("xxx");
p.setAdress("yyy");
p.setPhoneNumber("zzz");
EntityManagerFactory emf = javax.persistence.Persistence.createEntityManagerFactory("testPU");
EntityManager em = emf.createEntityManager();
em.getTransaction().begin();
try {
em.persist(p);
em.getTransaction().commit();
} catch (Exception e) {
e.printStackTrace();
em.getTransaction().rollback();
}
em.close();
emf.close();
}
}
At this point I have a table with one row (with written "xxx-yyy-zzz"). How can I add new row? Creating new Person doesn't work because it creates new table... I only find solution using Session and SessionFactory but I'm not able to use it, because I can't understand how generate a hibernate.cfg.xml (and in general how to create a session object).
Is There a solution using only EntityManager? Or how can I generate/write a hibernate.cfg.xml file? Is there a way to generate automatically it using netbeans?
EDIT: this is my persistence.xml file. Where do I have to put the ? I put it in the *** zone but it doesn't work...
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
<persistence-unit name="testPU" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<class>test.Person</class>
<properties>
<property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/stackoverflow?zeroDateTimeBehavior=convertToNull"/>
<property name="javax.persistence.jdbc.user" value="root"/>
<property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver"/>
<property name="javax.persistence.jdbc.password" value="leonida95."/>
<property name="hibernate.cache.provider_class" value="org.hibernate.cache.NoCacheProvider"/>
<property name="javax.persistence.schema-generation.database.action" value="create"/>
*****
</properties>
</persistence-unit>
</persistence>

Inside your Persistence Unit file you'll have something like
<properties>
<property name="hibernate.connection.url" value="..." />
<property name="hibernate.connection.driver_class" value="..."/>
...
</properties>
To create tables when the EntityManagerFactory is constructed, just add
<property name="hibernate.hbm2ddl.auto" value="create" />
Your code works fine.
You can call persist as many times as you want, and it will add rows to the target table.
em.persist(person1);
em.persist(person2);
...
persist does not create a table.

No persistence provider for Entity Manager with Tomcat

I'm trying to to develop a simple rest API project with Java and Tomcat. The HTTP request works correctly, but I'm figuring out a lot of problem by implementing a database MySQL to store data. This is my persistence.xml file, that is located in Java Resources/META-INF:
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
version="2.0">
<persistence-unit name="PERSISTENCE">
<description> Hibernate JPA Configuration Example</description>
<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
<class>com.resourceserver.Person</class>
<properties>
<property name="javax.persistence.jdbc.driver" value="com.mysql.cj.jdbc.Driver" />
<property name="javax.persistence.jdbc.url"
value="jdbc:mysql://localhost:3306/RESTResourceServer" />
<property name="javax.persistence.jdbc.user" value="root" />
<property name="javax.persistence.jdbc.password" value="password" />
<property name="hibernate.show_sql" value="true" />
<property name="hibernate.hbm2ddl.auto" value="update" />
</properties>
</persistence-unit>
This is my PersonDAO.java and JPAUtil.java class:
public class PersonDao {
EntityManager entityManager;
public PersonDao() {
entityManager = JPAUtil.getEntityManagerFactory().createEntityManager();
}
public void storePerson(Person person) {
entityManager.persist(person);
// people.add(person);
}
public void deletePerson(Person person) {
entityManager.remove(person);
// people.remove(person);
}
public Person findPersonId(int id) {
/*
* for (Person person : people) { if (person.getId() == id) { return person; } }
*/
return null;
}
#SuppressWarnings("unchecked")
public List<Person> getAllUsers() {
Query query = entityManager.createQuery("Select p From People p ");
return query.getResultList();
// return people;
}
}
public class JPAUtil {
private static final String PERSISTENCE_UNIT_NAME = "PERSISTENCE";
private static EntityManagerFactory factory;
public static EntityManagerFactory getEntityManagerFactory() {
if (factory == null) {
factory = Persistence.createEntityManagerFactory(PERSISTENCE_UNIT_NAME);
}
return factory;
}
public static void shutdown() {
if (factory != null) {
factory.close();
}
}
}
And in my Endpoint I simple use PersonDao persona = new PersonDao() to perform the operations; where am I wrong?

You are missing the persistence provider (no surprise there!)
Most likely you have added the JPA API as a dependency but forgot to add a concrete implementation like Hibernate or EclipseLink. This means you can compile the whole thing because the interfaces for JPA are there but there are not implementing classes.

Problems building up Java project with JPA

I am trying to get a javax.persistence running, but I get erros.
I built up a little project for testing, creating an entity class, the persistence.xml, and the running process:
Entity class:
package glasses;
import java.io.Serializable;
import javax.persistence.Entity;
import javax.persistence.Id;
#Entity
public class Hund implements Serializable {
#Id
private long id;
private String name;
private String typ;
public long getId() {
return this.id;
}
public void setId(long id) {
this.id = id;
}
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
public String getTyp() {
return this.typ;
}
public void setTyp(String typ) {
this.typ = typ;
}
}
persistence.xml:
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
<persistence-unit name="GlassesPU" transaction-type="RESOURCE_LOCAL">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<properties>
<property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/glasses?zeroDateTimeBehavior=convertToNull"/>
<property name="javax.persistence.jdbc.password" value="mypwd"/>
<property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver"/>
<property name="javax.persistence.jdbc.user" value="root"/>
<property name="javax.persistence.schema-generation.database.action" value="drop-and-create"/>
</properties>
</persistence-unit>
</persistence>
Error message:
Caused by: java.lang.IllegalArgumentException: Object: glasses.Hund#5d2e0422 is not a known entity type.
at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.registerNewObjectForPersist(UnitOfWorkImpl.java:4228)
at org.eclipse.persistence.internal.jpa.EntityManagerImpl.persist(EntityManagerImpl.java:496)
at glasses.FXMLDocumentController.handleButtonAction(FXMLDocumentController.java:48)
... 54 more
Does anyone know the problem? Is there anything wrong in the Hund-class? Or in the persistence.xml?

Use your Hund class inside your persistence.xml like following example. Just place it between the properties and the persistence-unit tags.
</properties>
<class>glasses.Hund</class>
</persistence-unit>

If you don't want to list in the persistence.xml all your entities you can add the following line in the persistence.xml:
<exclude-unlisted-classes>false</exclude-unlisted-classes>

Java Persistence Issue

I am trying to get a simple example up and running using JPA in an EJB through GlassFish. I have the following persistence.xml
<persistence version="1.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">
<persistence-unit name="default" transaction-type="RESOURCE_LOCAL">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<jta-data-source>jdbc/wms</jta-data-source>
<class>com.xxx.xxx.datamodel.MyTest</class>
<exclude-unlisted-classes />
<properties>
<property name="eclipselink.target-server" value="SunAS9"/>
<property name="eclipselink.logging.level" value="FINEST"/>
<property name="eclipselink.target-database" value="Oracle"/>
<property name="eclipselink.jdbc.driver" value="oracle.jdbc.OracleDriver" />
<property name="eclipselink.jdbc.url" value="[dbconnectionstring]" />
<property name="eclipselink.jdbc.user" value="user" />
<property name="eclipselink.jdbc.password" value="password" />
</properties>
</persistence-unit>
</persistence>
A simple entity:
package com.xxx.xxx.datamodel;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;
#Entity
#Table(name = "move_task")
public class MyTest {
private int key;
private String description;
#Id
public int getKey(){
return key;
}
public void setKey(int key){
this.key = key;
}
public String getDescription(){
return this.description;
}
public void setDescription(String description){
this.description = description;
}
#Override
public String toString(){
return "Key: " + key + " Description: " + description;
}
}
And finally the following code to try use the above:
private void jpaCall() {
try{
emf = Persistence.createEntityManagerFactory("default");
em = emf.createEntityManager();
log.info("JPA init complete");
final List<MyTest> list = em.createQuery("select p from MyTest p").getResultList();
for (MyTest current : list) {
final String description = current.getDescription();
log.info("JPA: Desc: " + description);
}
}
catch(Exception e){
log.error("Error on JPA", e);
}
}
When this is run as part of my EJB initialisation I get the following error:
java.lang.IllegalArgumentException: An exception occurred while creating a query in EntityManager:
Exception Description: Error compiling the query [select p from MyTest p]. Unknown entity type [MyTest].
...
Caused by: Exception [EclipseLink-8034] (Eclipse Persistence Services - 2.0.0.v20091127-r5931): org.eclipse.persistence.exceptions.JPQLException
Exception Description: Error compiling the query [select p from MyTest p]. Unknown entity type [MyTest].
I am not sure what I am doing wrong and would appreciate any help.
Cheers,
James

So as the comments above suggest this seems to be an issue with the eclipse plug in for glassfish. I am having no problems when deploying the ear manually.
Thanks all for the help.
James