spring - hibernate 5 naming strategy configuration - spring

Question

I am writing application using postgresql database and spring + hibernate frameworks.
I upgraded spring framework from 4.1.5.RELEASE to 4.2.0.RELEASE version and upgraded hibernate framework from 4.3.7.Final to 5.0.0.Final version.
After upgrade I have problems with NamingStrategy. In postgresql database, table column names are in lowercase separated by underscore, in application layer, bean properties are in camelcase.
This is working spring configuration file for older version:
<?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>
After upgrade I changed NamingStrategy configuration:
<entry key="hibernate.ejb.naming_strategy" value="org.hibernate.cfg.ImprovedNamingStrategy" />
like this:
<entry key="hibernate.implicit_naming_strategy" value="***" />
and tried all variants of options listed in hibernate javadoc: https://docs.jboss.org/hibernate/orm/5.0/javadocs/org/hibernate/cfg/AvailableSettings.html#IMPLICIT_NAMING_STRATEGY
but with no success.
Can you tell me what is alternative of ImprovedNamingStrategy in Hibernate 5 and provide a working configuration example ?

Answer 1

I think I found the solution.
To achieve my goal, I used hibernate.physical_naming_strategy configuration, instead of hibernate.implicit_naming_strategy.
I created an implementation of the PhysicalNamingStrategy interface which simulates part of the functionality of the original ImprovedNamingStrategy class:
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);
}
}
After I created this class, I changed my configuration from:
<entry key="hibernate.ejb.naming_strategy" value="org.hibernate.cfg.ImprovedNamingStrategy" />
to this:
<entry key="hibernate.physical_naming_strategy" value="fms.util.hibernate.ImprovedNamingStrategy" />
and now everything works correctly.
This solution covers only small part of ImprovedNamingStrategy. In my project, for table mapping and join mapping, I always specify the name of table or join column explicitly. I rely on implicit name conversion only for column names. So this simple solution was acceptable for me.
This is a full example of my Spring configuration file:
<?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>
I hope this solution will be helpful for somebody. :)

Answer 2

For anyone looking for a Java Config Solution
The hibernate.ejb.naming_strategy property seems split into two parts in hibernate 5.X:
hibernate.physical_naming_strategy
hibernate.implicit_naming_strategy
Spring provides SpringImplicitNamingStrategy and SpringPhysicalNamingStrategy for this purpose.
Here is my approach:
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

I had the exactly same problem. I fixed it with default implementation from spring boot:
<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

This work for me, from 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

try this:
#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

Please find below 3 points that I discovered while working on Naming Strategy:
If you are providing #Table and #Column annotation in your entity classes with names provided with an underscore i.e. user_id i.e. #Column(name="user_id"), it will take the column name as user_id; if you give it as userid then it will change to user_id if you use no strategy or implicit strategy (specifically org.hibernate.boot.model.naming.ImplicitNamingStrategyLegacyHbmImpl). So, if you want a strategy where the entity attribute name changes to one with underscore and lowercase letters i.e. something from userId to user_id, you should use implicit or no strategy (which actually uses implicit strategy).
If you don't want your naming strategy to add an underscore to the column name or class name, then the strategy that you need to use would look like:
spring.jpa.hibernate.naming.physical-strategy=org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl. The things that you provide in annotations #Table and #Column’s name attribute would remain as it is.
If you don't want to provide annotations and want to manually handle the table name and column names, you should extend the class org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl and override the required methods. If you still use annotations for some of the cases here, remember the overridden methods will apply on the names written in those annotations.