Hibernate4.3.x Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set-蒲公英云

      如下错误
            Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set。
                    今天没事看看新的hibernate-core-4.3.10.Final   看来官方文档。
public class Person {    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 int getPassword() {
 return password;
 }
 public void setPassword(int password) {
 this.password = password;
 }
 public Date getBirthday() {
 return birthday;
 }
 public void setBirthday(Date birthday) {
 this.birthday = birthday;
 }
   private Integer id;
   private String name;
   private int password;
   private Date birthday;
}
<?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">
<!-- 持久化映射文件（将java对象映射到数据库表） -->
<hibernate-mapping>
   <class name="com.it.hibernate.pojo.Person" table="t_person">
     <id name="id">
        <generator class="native"></generator>
     </id>
     <property name="name" column="t_name" length="12"/>
     <property name="password" length="6"/>
     <property name="birthday" />
   </class> 
</hibernate-mapping>
官方获取sessionfactory
public class HibernateUtil {
    private static final SessionFactory sessionFactory = buildSessionFactory();
    private static SessionFactory buildSessionFactory() {
        try {
            // Create the SessionFactory from hibernate.cfg.xml
            return new Configuration().configure().buildSessionFactory(
                new StandardServiceRegistryBuilder().build() );
        }
        catch (Throwable ex) {
            // Make sure you log the exception, as it might be swallowed
            System.err.println("Initial SessionFactory creation failed." + ex);
            throw new ExceptionInInitializerError(ex);
        }
    }
    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
}
hibernate.cfg.xml 如下
<?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:///hibernate_db</property>
        <property name="hibernate.connection.username">root</property>
        <property name="hibernate.connection.password">123456</property>
        <!-- 数据库方言 加五提高速度 -->
        <property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>
        <!-- 展现sql -->
        <property name="show_sql">true</property>
        <!-- 格式化sql -->
        <property name="hibernate.format_sql">true</property>
        <!-- 自动创建sql create 每次执行都都要先删除表再创建表 update 没有就创建表 有就直接插入 -->
        <property name="hibernate.hbm2ddl.auto">update</property>
        <mapping resource="com/it/hibernate/pojo/Person.hbm.xml" />
    </session-factory>
 </hibernate-configuration>
测试类
public class PersonTest {
 public static void main(String[] args) {
   SessionFactory factory =HibernateUtil.getSessionFactory();
   Session session = factory.openSession();
   Transaction tx =   session.beginTransaction();
   Person p = new Person();
   p.setName("MOMO");
   p.setPassword(123456);
   p.setBirthday(new Date());
   session.save(p);
   tx.commit();
   session.close();
 }
}
如下错误
Initial SessionFactory creation failed.org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set
Exception in thread "main" java.lang.ExceptionInInitializerError
 at com.it.hibernate.utils.HibernateUtil2.buildSessionFactory(HibernateUtil2.java:21)
 at com.it.hibernate.utils.HibernateUtil2.<clinit>(HibernateUtil2.java:9)
 at com.it.hibernate.pojo.test.PersonTest.main(PersonTest.java:14)
Caused by: org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set
 at org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl.determineDialect(DialectFactoryImpl.java:104)
 at org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl.buildDialect(DialectFactoryImpl.java:71)
 at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:209)
 at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:111)
 at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:234)
 at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:206)
 at org.hibernate.cfg.Configuration.buildTypeRegistrations(Configuration.java:1887)
 at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1845)
 at com.it.hibernate.utils.HibernateUtil2.buildSessionFactory(HibernateUtil2.java:16)
 ... 2 more
修改获取sessionFactory的公用方法
public class HibernateUtil {
    private static final SessionFactory sessionFactory = buildSessionFactory();
    private static SessionFactory buildSessionFactory() {
        try {
            // 从 hibernate.cfg.xml 创建SessionFactory
        Configuration cfg = new Configuration().configure();         StandardServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()             .applySettings(cfg.getProperties()).build();             return cfg.buildSessionFactory(             serviceRegistry);
        }
        catch (Throwable ex) {
            System.err.println("Initial SessionFactory creation failed." + ex);
            throw new ExceptionInInitializerError(ex);
        }
    }
    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
}
修改完就可以顺利插入数据。 有个疑问是官方给错了？还是我其他地方有问题有问题呢！ 但是我改了sessionfactory获取方式就好了呀！求大神指点。
private static final SessionFactory sessionFactory = buildSessionFactory();
    private static SessionFactory buildSessionFactory() {
        try {
            // Create the SessionFactory from hibernate.cfg.xml
            return new Configuration().configure().buildSessionFactory(
                new StandardServiceRegistryBuilder().build() );
        }
        catch (Throwable ex) {
            // Make sure you log the exception, as it might be swallowed
            System.err.println("Initial SessionFactory creation failed." + ex);
            throw new ExceptionInInitializerError(ex);
        }
    }
    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
}