MongoDB 的休眠配置

Hibernate configuration with MongoDB

我一直在尝试使用 MongoDB 和 Java 中的 Hibernate。我在使用它的配置文件时遇到了一些问题。

我过去已经将 Hibernate 与 SQL 数据库一起使用,但似乎 MongoDB 的配置文件必须完全不同。

根据 this documentation,它应该看起来像这样:

<?xml version="1.0" encoding="UTF-8"?>
<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="eshop" transaction-type="JTA">
        <provider>org.hibernate.ogm.jpa.HibernateOgmPersistence</provider>
        <class>org.hsnr.rest.domain.entities.Address</class>
        <class>org.hsnr.rest.domain.entities.Order</class>
        <class>org.hsnr.rest.domain.entities.Person</class>
        <class>org.hsnr.rest.domain.entities.Product</class>
        <class>org.hsnr.rest.domain.entities.User</class>
        <properties>
            <property name="hibernate.transaction.jta.platform"
                            value="org.hibernate.service.jta.platform.internal.JBossStandAloneJtaPlatform" />
            <property name="hibernate.ogm.datastore.provider"
                            value="mongodb" />
        </properties>
    </persistence-unit>
</persistence>

但是,当我尝试使用

创建会话时

new Configuration().configure().buildSessionFactory();

我收到以下错误:

org.hibernate.internal.util.config.ConfigurationException: Unable to perform unmarshalling at line number 5 and column 28 in RESOURCE hibernate.cfg.xml. Message: cvc-elt.1: Cannot find the declaration of element 'persistence'.

是我的方法有误还是我忽略了什么?

您可以像下面这样为您的配置尝试基本测试设置。

EntityManagerFactory entityManagerFactory = Persistence.createEntityManagerFactory( "eshop" );
EntityManager entityManager = entityManagerFactory.createEntityManager();
entityManager.getTransaction().begin();
// perform operations here
entityManager.getTransaction().commit();
entityManager.close();
entityManagerFactory.close();

使用下面的代码:

<hibernate-configuration
    xmlns="http://www.hibernate.org/xsd/hibernate-configuration"
    xsi:schemaLocation="http://www.hibernate.org/xsd/hibernate-configuration hibernate-configuration-4.0.xsd"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

来自 configure() 的 javadoc:

Use the mappings and properties specified in an application resource named hibernate.cfg.xml.

您设置的是 persistence.xml。使用 using javax.persistence.Persistence 应该有效:

EntityManagerFactory emf = Persistence.createEntityManagerFactory( "eshop" );

如果由于某种原因您需要会话工厂,但您使用的是 JPA,则可以使用 unwrap() 方法

获取它
SessionFactory sf = emf.unwrap( SessionFactory.class );    

更新: 您还可以以编程方式创建工厂,有一个 class OgmConfiguration(扩展 Configuraiton):

    OgmConfiguration configuration = new OgmConfiguration();

    // This is optional, if you want to set some options using
    // a fluent API
    configuration.configureOptionsFor( MongoDB.class )
        .writeConcern( WriteConcernType.UNACKNOWLEDGED );

    SessionFactory sf = configuration
        .addAnnotatedClass( org.hsnr.rest.domain.entities.Address.class )
        // ... Other annotated classes
        .setProperty( OgmProperties.DATABASE, "mongodb_database" )
        .setProperty( OgmProperties.DATASTORE_PROVIDER, DatastoreProviderType.MONGODB.name() )

        // All this properties are optional, appropriate default will be used if missing
        .setProperty( OgmProperties.CREATE_DATABASE, "false" )
        .setProperty( OgmProperties.USERNAME, "username" )
        .setProperty( OgmProperties.PASSWORD, "password" )
        .setProperty( OgmProperties.HOST, "localhost:12897" )

        // Check MongoDBProperties for MongoDB specific options
        .setProperty( MongoDBProperties.AUTHENTICATION_MECHANISM, AuthenticationMechanismType.BEST.name() )

        .buildSessionFactory();

在此示例中,我添加了几个选项以提供概述,但如果您使用默认设置并且不需要身份验证,则只需要数据库名称和数据存储提供程序