Question

我在运行示例时遇到了一些问题。 hibernate和MySQL。

我按照下一个教程：http://www.javatutoriales.com/2009/05/hibernate-parte-2-persistiendo-objetos.html

我改变了一些读这篇文章的行。

hibernate.cfg.xml中：

<?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"> 

<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-core</artifactId>
    <version>5.2.10.Final</version>
</dependency>

<hibernate-configuration>

  <session-factory>
    <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
    <property name="connection.url"> jdbc:mysql://localhost:3306/base_prueba</property>
    <property name="connection.username">root</property>
    <property name="connection.password">tomazon-33</property>

    <property name="connection.pool_size">1</property>

    <property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>

    <property name="show_sql">true</property>
    <property name="hbm2ddl.auto">create-drop</property>



    <mapping class="mapeo/Contacto.hbm.xml"/>
  </session-factory>
</hibernate-configuration>

主：

package Main;

import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.transaction.HeuristicMixedException;
import javax.transaction.RollbackException;
import org.hibernate.HibernateException;

public class Main
{ 
    public static void main(String[] args) throws HibernateException 
    { 
        try {
            ContactosDAO contactosDAO = new ContactosDAO();
            Contacto contactoRecuperado = null;
            long idAEliminar = 0;

            Contacto contacto1 = new Contacto("Contacto 1", "contacto1@contacto.com", "12345678");
            Contacto contacto2 = new Contacto("Contacto 2", "contacto2@contacto.com", "87654321");
            Contacto contacto3 = new Contacto("Contacto 3", "contacto3@contacto.com", "45612378");


            idAEliminar = contactosDAO.guardaContacto(contacto1);
            contactosDAO.guardaContacto(contacto2);
            contactosDAO.guardaContacto(contacto3);

            contacto2.setNombre("Nuevo Contacto 2");
            contactosDAO.actualizaContacto(contacto2);

            contactoRecuperado = contactosDAO.obtenContacto(idAEliminar);
            System.out.println("Recuperamos a " + contactoRecuperado.getNombre());

            contactosDAO.eliminaContacto(contactoRecuperado);


            List<Contacto> listaContactos = contactosDAO.obtenListaContactos();
            System.out.println("Hay " + listaContactos.size() + "contactos en la base de datos");

            for(Contacto c : listaContactos)
            {
                System.out.println("-> " + c.getNombre()); 
            }
        } catch (RollbackException ex) {
            Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
        } catch (HeuristicMixedException ex) {
            Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
        }
    } 
}

Contactos：

package Main;

import java.io.Serializable;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name="contactos")
public class Contacto implements Serializable
{
    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    private long id;
    private String nombre;

    @Column(name="e_mail")
    private String email;
    private String telefono;

    public Contacto()
    {
    }

    public Contacto(String nombre, String email, String telefono)
    {
        this.nombre = nombre;
        this.email = email;
        this.telefono = telefono;
    }

    public String getEmail()
    {
        return email;
    }

    public void setEmail(String email)
    {
        this.email = email;
    }

    public long getId()
    {
        return id;
    }

    private void setId(long id)
    {
        this.id = id;
    }

    public String getNombre()
    {
        return nombre;
    }

    public void setNombre(String nombre)
    {
        this.nombre = nombre;
    }

    public String getTelefono()
    {
        return telefono;
    }

    public void setTelefono(String telefono)
    {
        this.telefono = telefono;
    }
}

Contactos-DAO：

public class ContactosDAO
{  
 private Session sesion; 
 private Transaction tx;  

public long guardaContacto(Contacto contacto) throws HibernateException, RollbackException, HeuristicMixedException 
    { 
        long id = 0;  

        try 
        { 
            iniciaOperacion(); 
            id = (Long) sesion.save(contacto); 
            tx.commit();
        } catch (HibernateException he) 
        { 
            try {
                manejaExcepcion(he); 
                throw he;
            } catch (IllegalStateException | SystemException ex) {
                Logger.getLogger(ContactosDAO.class.getName()).log(Level.SEVERE, null, ex);
            }
        } catch (HeuristicRollbackException | SecurityException | SystemException ex) {
            Logger.getLogger(ContactosDAO.class.getName()).log(Level.SEVERE, null, ex);
        } finally 
        { 
            sesion.close(); 
        }  

        return id;
}

的HibernateUtil：

package hibernatenormal;

import org.hibernate.HibernateException;
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 (HibernateException he) 
        { 
           System.err.println("Ocurrió un error en la inicialización de la SessionFactory: " + he); 
           throw new ExceptionInInitializerError(he); 
        } 
    }  

    public static SessionFactory getSessionFactory() 
    { 
        return sessionFactory; 
    } 
}

错误：

run:
jul 24, 2017 8:03:07 PM org.hibernate.Version logVersion
INFO: HHH000412: Hibernate Core {5.2.10.Final}
jul 24, 2017 8:03:07 PM org.hibernate.cfg.Environment <clinit>
INFO: HHH000206: hibernate.properties not found
jul 24, 2017 8:03:07 PM org.hibernate.boot.jaxb.internal.stax.LocalXmlResourceResolver resolveEntity
WARN: HHH90000012: Recognized obsolete hibernate namespace http://hibernate.sourceforge.net/hibernate-configuration. Use namespace http://www.hibernate.org/dtd/hibernate-configuration instead.  Support for obsolete DTD/XSD namespaces may be removed at any time.
Ocurrió un error en la inicialización de la SessionFactory: org.hibernate.internal.util.config.ConfigurationException: Unable to perform unmarshalling at line number -1 and column -1 in RESOURCE hibernate.cfg.xml. Message: cvc-elt.1: No se ha encontrado la declaración del elemento 'dependency'.
Exception in thread "main" java.lang.NullPointerException
    at Main.ContactosDAO.guardaContacto(ContactosDAO.java:59)
    at Main.Main.main(Main.java:34)
C:\Users\User\AppData\Local\NetBeans\Cache\8.2\executor-snippets\run.xml:53: Java returned: 1
BUILD FAILED (total time: 1 second)

Answer 1

删除hibernate.cfg.xml上的<dependency>标记。

删除这些行：

<dependency>
  <groupId>org.hibernate</groupId>
  <artifactId>hibernate-core</artifactId>
  <version>5.2.10.Final</version>
</dependency>

<dependency>标记应放在你的maven pom.xml上

配置hibernate 5.2.10时出错

1 个答案: