spring - hibernate 5 命名策略配置

Question

我正在使用 postgresql 数据库和 spring + hibernate 框架编写应用程序。

我将spring框架从4.1.5.RELEASE升级到4.2.0.RELEASE版本，将hibernate框架从4.3.7.Final升级到5.0.0.Final版本。

升级后我遇到了 NamingStrategy 的问题。在postgresql数据库中，表列名是小写，下划线分隔，在应用层，bean属性是驼峰式。

这是旧版本的工作弹簧配置文件：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns="http://www.springframework.org/schema/beans"
       xmlns:p="http://www.springframework.org/schema/p"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/tx
        http://www.springframework.org/schema/tx/spring-tx.xsd">

    <context:component-scan base-package="fms" />

    <bean id="microFmsDataSource" class="org.apache.tomcat.jdbc.pool.DataSource" destroy-method="close">
        <property name="driverClassName" value="org.postgresql.Driver" />
        <property name="url" value="***" />
        <property name="username" value="***" />
        <property name="password" value="***" />

        <property name="testOnBorrow" value="true" />
        <property name="testOnReturn" value="true" />
        <property name="testWhileIdle" value="true" />
        <property name="validationQuery" value="select 1" />
        <property name="initialSize" value="5" />
        <property name="minIdle" value="10" />
        <property name="maxIdle" value="100" />
        <property name="maxActive" value="100" />
        <property name="removeAbandoned" value="true" />
    </bean>

    <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <property name="dataSource" ref="microFmsDataSource"/>

        <property name="packagesToScan">
            <list>
                <value>fms</value>
            </list>
        </property>

        <property name="jpaVendorAdapter">
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter" />
        </property>

        <property name="jpaPropertyMap">
            <map>
                <entry key="hibernate.cache.provider_class" value="org.hibernate.cache.NoCacheProvider" />
                <entry key="hibernate.hbm2ddl.auto" value="validate" />
                <entry key="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect" />
                <entry key="hibernate.show_sql" value="true" />
                <entry key="hibernate.format_sql" value="true" />
                <entry key="hibernate.ejb.naming_strategy" value="org.hibernate.cfg.ImprovedNamingStrategy" />
            </map>
        </property>
    </bean>

    <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
        <property name="entityManagerFactory" ref="entityManagerFactory" />
    </bean>

    <tx:annotation-driven transaction-manager="transactionManager"/>
</beans>

升级后我更改了 NamingStrategy 配置：

<entry key="hibernate.ejb.naming_strategy" value="org.hibernate.cfg.ImprovedNamingStrategy" />

像这样：

<entry key="hibernate.implicit_naming_strategy" value="***" />

并尝试了 hibernate javadoc 中列出的所有选项变体：https://docs.jboss.org/hibernate/orm/5.0/javadocs/org/hibernate/cfg/AvailableSettings.html#IMPLICIT_NAMING_STRATEGY

但没有成功。

您能告诉我在 Hibernate 5 中改进命名策略的替代方法是什么，并提供一个有效的配置示例吗？

Answer 1

我想我找到了解决办法。

为了实现我的目标，我使用了hibernate.physical_naming_strategy 配置，而不是hibernate.implicit_naming_strategy。

我创建了一个PhysicalNamingStrategy 接口的实现，它模拟了原始ImprovedNamingStrategy 类的部分功能：

package fms.util.hibernate;

import org.apache.commons.lang.StringUtils;
import org.hibernate.boot.model.naming.Identifier;
import org.hibernate.boot.model.naming.PhysicalNamingStrategy;
import org.hibernate.engine.jdbc.env.spi.JdbcEnvironment;

public class ImprovedNamingStrategy implements PhysicalNamingStrategy {

    @Override
    public Identifier toPhysicalCatalogName(Identifier identifier, JdbcEnvironment jdbcEnv) {
        return convert(identifier);
    }

    @Override
    public Identifier toPhysicalColumnName(Identifier identifier, JdbcEnvironment jdbcEnv) {
        return convert(identifier);
    }

    @Override
    public Identifier toPhysicalSchemaName(Identifier identifier, JdbcEnvironment jdbcEnv) {
        return convert(identifier);
    }

    @Override
    public Identifier toPhysicalSequenceName(Identifier identifier, JdbcEnvironment jdbcEnv) {
        return convert(identifier);
    }

    @Override
    public Identifier toPhysicalTableName(Identifier identifier, JdbcEnvironment jdbcEnv) {
        return convert(identifier);
    }

    private Identifier convert(Identifier identifier) {
        if (identifier == null || StringUtils.isBlank(identifier.getText())) {
            return identifier;
        }

        String regex = "([a-z])([A-Z])";
        String replacement = "$1_$2";
        String newName = identifier.getText().replaceAll(regex, replacement).toLowerCase();
        return Identifier.toIdentifier(newName);
    }
}

创建这个类后，我将配置更改为：

<entry key="hibernate.ejb.naming_strategy" value="org.hibernate.cfg.ImprovedNamingStrategy" />

到这里：

<entry key="hibernate.physical_naming_strategy" value="fms.util.hibernate.ImprovedNamingStrategy" />

现在一切正常。

此解决方案仅涵盖ImprovedNamingStrategy 的一小部分。在我的项目中，对于表映射和连接映射，我总是明确指定表或连接列的名称。我仅对列名依赖隐式名称转换。所以这个简单的解决方案对我来说是可以接受的。

这是我的 Spring 配置文件的完整示例：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns="http://www.springframework.org/schema/beans"
       xmlns:p="http://www.springframework.org/schema/p"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/tx
        http://www.springframework.org/schema/tx/spring-tx.xsd">

    <context:component-scan base-package="fms" />

    <bean id="microFmsDataSource" class="org.apache.tomcat.jdbc.pool.DataSource" destroy-method="close">
        <property name="driverClassName" value="org.postgresql.Driver" />
        <property name="url" value="***" />
        <property name="username" value="***" />
        <property name="password" value="***" />

        <property name="testOnBorrow" value="true" />
        <property name="testOnReturn" value="true" />
        <property name="testWhileIdle" value="true" />
        <property name="validationQuery" value="select 1" />
        <property name="initialSize" value="5" />
        <property name="minIdle" value="10" />
        <property name="maxIdle" value="100" />
        <property name="maxActive" value="100" />
        <property name="removeAbandoned" value="true" />
    </bean>

    <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <property name="dataSource" ref="microFmsDataSource"/>

        <property name="packagesToScan">
            <list>
                <value>fms</value>
            </list>
        </property>

        <property name="jpaVendorAdapter">
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter" />
        </property>

        <property name="jpaPropertyMap">
            <map>
                <entry key="hibernate.cache.provider_class" value="org.hibernate.cache.NoCacheProvider" />
                <entry key="hibernate.hbm2ddl.auto" value="validate" />
                <entry key="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect" />
                <entry key="hibernate.show_sql" value="true" />
                <entry key="hibernate.format_sql" value="true" />
                <entry key="hibernate.physical_naming_strategy" value="fms.util.hibernate.ImprovedNamingStrategy" />
            </map>
        </property>
    </bean>

    <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
        <property name="entityManagerFactory" ref="entityManagerFactory" />
    </bean>

    <tx:annotation-driven transaction-manager="transactionManager"/>
</beans>

我希望这个解决方案对某人有所帮助。 :)

Answer 2

对于任何寻找 Java 配置解决方案的人

hibernate.ejb.naming_strategy 属性在 hibernate 5.X 中似乎分为两部分：

hibernate.physical_naming_strategy

hibernate.implicit_naming_strategy

Spring为此提供了SpringImplicitNamingStrategy和SpringPhysicalNamingStrategy。

这是我的方法：

import javax.persistence.EntityManagerFactory;
import javax.sql.DataSource;

import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.orm.jpa.EntityManagerFactoryBuilder;
import org.springframework.boot.orm.jpa.hibernate.SpringImplicitNamingStrategy;
import org.springframework.boot.orm.jpa.hibernate.SpringPhysicalNamingStrategy;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.DependsOn;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;

@Configuration
@DependsOn("myDataSource")
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef = "myEntityManagerFactory",
        basePackages={"com.myapp.repo"},
        transactionManagerRef="myTransactionManager"
        )
public class MyJpaConfig {

    private Map<String, Object> properties;

    public MyJpaConfig() {
        properties = new HashMap<>();
        properties.put("hibernate.implicit_naming_strategy", SpringImplicitNamingStrategy.class.getName());
        properties.put("hibernate.physical_naming_strategy", SpringPhysicalNamingStrategy.class.getName());

    }

    @Bean(name = "myEntityManagerFactory")
    public LocalContainerEntityManagerFactoryBean entityManagerFactory(EntityManagerFactoryBuilder builder,
            @Qualifier("systemDataSource") DataSource dataSource) {
        LocalContainerEntityManagerFactoryBean build = builder.dataSource(dataSource)
                .packages("com.myapp.entity")
                .properties(properties)
                .build();
        return build;

    }

    @Bean(name = "myTransactionManager")
    public PlatformTransactionManager myTransactionManager(
            @Qualifier("myEntityManagerFactory") EntityManagerFactory myEntityManagerFactory) {
        return new JpaTransactionManager(myEntityManagerFactory);
    }
}

Answer 3

我遇到了完全相同的问题。我用spring boot的默认实现修复了它：

<property name="hibernate.implicit_naming_strategy" value="org.springframework.boot.orm.jpa.hibernate.SpringImplicitNamingStrategy" />
<property name="hibernate.physical_naming_strategy" value="org.springframework.boot.orm.jpa.hibernate.SpringPhysicalNamingStrategy" />

Answer 4

这对我有用，来自http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/orm/hibernate5/LocalSessionFactoryBean.html

<bean id="sessionFactory" 
    class="org.springframework.orm.hibernate5.LocalSessionFactoryBean">

    <!-- convert aaBb to aa_bb -->
    <property name="PhysicalNamingStrategy">
        <bean class="fms.util.hibernate.ImprovedNamingStrategy" />
    </property>

    <!-- convert aa_bb to aaBb -->
    <property name="ImplicitNamingStrategy">
        <bean class="org.hibernate.boot.model.naming.ImplicitNamingStrategyLegacyHbmImpl" />
    </property>
...
</bean>   

Answer 5

试试这个：

@Bean
public LocalSessionFactoryBean getSessionFactory() {
    LocalSessionFactoryBean localSessionFactoryBean = new LocalSessionFactoryBean();
    localSessionFactoryBean.setDataSource(getDataSource());
    localSessionFactoryBean.setHibernateProperties(getHibernateProperties());
    localSessionFactoryBean.setPackagesToScan(new String[]{"com.xxx.pojo"});
    // -----important-----
    localSessionFactoryBean.setPhysicalNamingStrategy(new CustomNamingStrategy());
    return localSessionFactoryBean;
}

public class CustomNamingStrategy extends PhysicalNamingStrategyStandardImpl {***

Answer 6

请找出我在研究命名策略时发现的以下 3 点：

1. 如果您在实体类中提供@Table 和@Column 注释，并且名称带有下划线，即user_id 即@Column(name="user_id")，它将采用列名作为user_id;如果您将其作为 userid 提供，那么如果您不使用策略或隐式策略（特别是 org.hibernate.boot.model.naming.ImplicitNamingStrategyLegacyHbmImpl），它将更改为 user_id。因此，如果您想要一个实体属性名称更改为带有下划线和小写字母的策略，即从 userId 到 user_id，您应该使用隐式或不使用策略（即实际上使用隐式策略）。

2. 如果您不希望您的命名策略在列名或类名中添加下划线，那么您需要使用的策略如下所示： spring.jpa.hibernate.naming.physical-strategy=org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl。您在注释 @Table 和 @Column’s 名称属性中提供的内容将保持原样。

3. 如果你不想提供注解，想手动处理表名和列名，你应该扩展类org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl并覆盖所需的方法。如果您仍然在此处的某些情况下使用注释，请记住，重写的方法将应用于这些注释中写入的名称。