HIbernate...EntityManagerFactoryProvider.createEntityManagerFactory

public class GeraTabelas {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		EntityManagerFactory factory = null;
	      factory =        Persistence.createEntityManagerFactory("exemploJPA1");
		
		System.out.println("gerou....");
	}

}
---

<persistence-unit name="exemploJPA1" transaction-type="RESOURCE_LOCAL">
  <provider>org.hibernate.ejb.HibernatePersistence</provider>
  <class>br.com.exemplojpa.modelo.Usuario</class>
    <properties>
      <property name="hibernate.archive.autodetection" value="class"/>
      <property name="hibernate.connection.driver_class"  value="com.mysql.jdbc.Driver" />
      <property name="hibernate.connection.url"  value="jdbc:mysql://localhost:3306/exemplojpa" />
      <property name="hibernate.connection.username" value="root"/>
      <property name="hibernate.connection.password" value="root"/>
      <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect" />
      <property name="hibernate.show_sql" value="true" />
      <property name="hibernate.hbm2ddl.auto" value="create" />
    </properties>
  </persistence-unit>

---

@Entity
public class Usuario {

	@Id
	@GeneratedValue(strategy = GenerationType.IDENTITY)
	private Integer id;

	@Column
	private String login;

	@Column
	private String password;

	@Column

	private String nome;

<persistence-unit name="exemploJPA1" transaction-type="RESOURCE_LOCAL">
  <provider>org.hibernate.ejb.HibernatePersistence</provider>
   <class>br.com.exemplojpa.modelo.Usuario</class>
    <class>br.com.exemplojpa.modelo.Centro</class>
    <class>br.com.exemplojpa.modelo.Universidade</class>
    <properties>
      <property name="hibernate.archive.autodetection" value="class"/>
      <property name="hibernate.connection.driver_class"  value="com.mysql.jdbc.Driver" />
      <property name="hibernate.connection.url"  value="jdbc:mysql://localhost:3306/exemplojpa" />
      <property name="hibernate.connection.username" value="root"/>
      <property name="hibernate.connection.password" value="root"/>
      <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect" />
      <property name="hibernate.show_sql" value="true" />
      <property name="hibernate.hbm2ddl.auto" value="create-tables" />
    </properties>
  </persistence-unit>

---

Exception in thread "main" java.lang.NullPointerException
	at oracle.toplink.essentials.ejb.cmp3.EntityManagerFactoryProvider.createEntityManagerFactory(EntityManagerFactoryProvider.java:120)
	at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:52)
	at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:34)
	at br.com.exemplojpa.persistencia.UsuarioDAO.<init>(UsuarioDAO.java:25)
	at br.com.exemplojpa.negocio.UsuarioBusiness.inserirUsuario(UsuarioBusiness.java:20)
	at br.com.exemplojpa.teste.TesteExemploJPA.main(TesteExemploJPA.java:39)

--

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.EntityTransaction;
import javax.persistence.Persistence;

import br.com.exemplojpa.modelo.Usuario;

/**
 * 
 * 
 * 
 * 
 * 
 * 
 */
public class UsuarioDAO {

	private EntityManagerFactory factory = null;

	private EntityManager manager = null;

	public UsuarioDAO() {
		factory = Persistence.createEntityManagerFactory("exemploJPA1");
		manager = factory.createEntityManager();
	}

	/**
	 * Inserindo um usuário
	 * 
	 * @param usuario
	 */
	public void inserirUsuario(Usuario usuario) {

		EntityTransaction transaction = manager.getTransaction();

		try {
			transaction.begin();

			manager.persist(usuario);

			transaction.commit();

		} catch (Exception e) {
			transaction.rollback();

			System.err.println("Erro: " + e.getMessage());

		} finally {
			manager.close();
		}

	}

	/**
	 * Pesquisar um usuário
	 * 
	 * @param usuario
	 */
	public Usuario pesquisarUsuario(Integer id, Usuario usuario) {
		EntityTransaction transaction = manager.getTransaction();

		Usuario retorno = null;

		try {

			transaction.begin();

			retorno = (Usuario) manager.find(Usuario.class, id);

		} catch (Exception e) {
			transaction.rollback();

			System.err.println("Erro: " + e.getMessage());
		} finally {
			manager.close();
		}

		return retorno;

	}

}
---
**
 * 
 * 
 * 
 * 
 * 
 * 
 */
public class TesteExemploJPA {

	public static void main(String[] args) {
		/*
		 * Criando o objeto usuário
		 */
		Usuario usuario = new Usuario();
		
		usuario.setLogin("mary");
		usuario.setPassword("mary");
		usuario.setNome("lock");
		
		
		
		
		/*
		 * Instanciando a classe de negócio
		 */
		UsuarioBusiness usuarioBusiness = new UsuarioBusiness();

		/*
		 * Inserindo um usuário no banco
		 */
		usuarioBusiness.inserirUsuario(usuario);

		/*
		 * Pesquisando o usuário inserido no banco
		 */

		
		
		Usuario usuarioBanco = new Usuario();

		usuarioBanco = usuarioBusiness.pesquisarUsuario(usuario);

		/*
		 * Mostrando o resultado da consulta no banco
		 */
		System.out.println();
		System.out.println("         Exemplo JPA         ");
		System.out.println("Id: " + usuarioBanco.getId());
		System.out.println("Login: " + usuarioBanco.getLogin());
		System.out.println("Senha: " + usuarioBanco.getPassword());
		System.out.println("Nome: " + usuarioBanco.getNome());

	}

}

<persistence-unit name="exemploJPA1" transaction-type="RESOURCE_LOCAL">
  <provider>oracle.toplink.essentials.ejb.cmp3.EntityManagerFactoryProvide</provider>
  <class>br.com.exemplojpa.modelo.Usuario</class>
    
    <properties>
        <property name="toplink.jdbc.url" value="jdbc:mysql://localhost:3306/exemplojpa" />
        <property name="toplink.jdbc.user" value="root"/>
        <property name="toplink.jdbc.driver" value="com.mysql.jdbc.Driver"/>
       <property name="toplink.jdbc.password" value="root"/>
      </properties>
    </persistence-unit>
</persistence>