HibernateException: Access to DialectResolutionInfo cannot be null when ‘hibernate.dialect‘ not set

矫情吗；* 2023-10-10 19:33 17阅读 0赞

> **Hibernate 启动报错系列**  
> （一）缺少数据库的方言配置：[Caused by: org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when ‘hibernate.dialect’ not set][Caused by_ org.hibernate.HibernateException_ Access to DialectResolutionInfo cannot be null when _hibernate.dialect_ not set]  
> （二）缺少数据库的用户名和密码配置：[Caused by: java.sql.SQLException: Access denied for user ‘‘@‘localhost‘ (using password: NO)][Caused by_ java.sql.SQLException_ Access denied for user _localhost_ _using password_ NO]

### 文章目录 ###

*  一、报错问题
 *  二、问题背景
 *  三、原因分析
 *  四、解决方案

# 一、报错问题 #

Caused by: org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when ‘hibernate.dialect’ not set  
![在这里插入图片描述][db12c485186e4013bad1b4650d222461.png]

# 二、问题背景 #

新建Java项目，并添加 Hibernate 框架支持，启动测试（运行默认的Main类中的main()方法），出现报错。

Main.java

import org.hibernate.HibernateException;
    import org.hibernate.Metamodel;
    import org.hibernate.query.Query;
    import org.hibernate.Session;
    import org.hibernate.SessionFactory;
    import org.hibernate.cfg.Configuration;
    
    import javax.persistence.metamodel.EntityType;
    
    import java.util.Map;
    
    public class Main {
        
        private static final SessionFactory ourSessionFactory;
    
        static {
        
            try {
        
                Configuration configuration = new Configuration();
                configuration.configure();
    
                ourSessionFactory = configuration.buildSessionFactory();
            } catch (Throwable ex) {
        
                throw new ExceptionInInitializerError(ex);
            }
        }
    
        public static Session getSession() throws HibernateException {
        
            return ourSessionFactory.openSession();
        }
    
        public static void main(final String[] args) throws Exception {
        
            final Session session = getSession();
            try {
        
                System.out.println("querying all the managed entities...");
                final Metamodel metamodel = session.getSessionFactory().getMetamodel();
                for (EntityType<?> entityType : metamodel.getEntities()) {
        
                    final String entityName = entityType.getName();
                    final Query query = session.createQuery("from " + entityName);
                    System.out.println("executing: " + query.getQueryString());
                    for (Object o : query.list()) {
        
                        System.out.println("  " + o);
                    }
                }
            } finally {
        
                session.close();
            }
        }
    }

hibernate.cfg.xml

<?xml version='1.0' encoding='utf-8'?>
    <!DOCTYPE hibernate-configuration PUBLIC
            "-//Hibernate/Hibernate Configuration DTD//EN"
            "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
    <hibernate-configuration>
        <session-factory>
            <property name="connection.url">jdbc:mysql://localhost:3306/hibernate_test</property>
            <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
            
            <property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>
            <mapping class="com.hibernate.helloworld.TblAccountEntity"/>
            
            
    
            
            
    
    
        </session-factory>
    </hibernate-configuration>

# 三、原因分析 #

缺少数据库方言配置。

# 四、解决方案 #

在 Hibernate 的配置文件 hibernate.cfg.xml 中，添加数据库方言配置。MySQL的方言配置如下所示：

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

完整示例如下：  
hibernate.cfg.xml

[Caused by_ org.hibernate.HibernateException_ Access to DialectResolutionInfo cannot be null when _hibernate.dialect_ not set]: https://blog.csdn.net/Shipley_Leo/article/details/130795242
[Caused by_ java.sql.SQLException_ Access denied for user _localhost_ _using password_ NO]: https://blog.csdn.net/Shipley_Leo/article/details/130805476
[db12c485186e4013bad1b4650d222461.png]: https://img-blog.csdnimg.cn/db12c485186e4013bad1b4650d222461.png