Spring Boot 配置 : HibernateJpaConfiguration

概述

HibernateJpaAutoConfiguration是Spring Boot针对Spring Data JPA + Hibernate组合使用的自动配置类。不过HibernateJpaAutoConfiguration主要的配置工作，并非自己完成的，而是通过导入的配置类HibernateJpaConfiguration来完成。就配置类HibernateJpaConfiguration而言，它继承自JpaBaseConfiguration,它自身所做的工作也不是很多，主要是提供针对JPA实现Hibernate的一些供应商实现信息。而真正的配置效果，主要在于其基类JpaBaseConfiguration。

源代码

源代码版本 : spring-boot-autoconfigure-2.1.3.RELEASE

package org.springframework.boot.autoconfigure.orm.jpa;

// 省略 import 行

/**
 * JpaBaseConfiguration implementation for Hibernate.
 *
 */
@Configuration
// 确保前缀为 spring.jpa.hibernate 的配置属性项加载到 bean HibernateProperties
@EnableConfigurationProperties(HibernateProperties.class)
// 仅在只有一个 bean DataSource 的条件下生效
@ConditionalOnSingleCandidate(DataSource.class)
class HibernateJpaConfiguration extends JpaBaseConfiguration {

	private static final Log logger = LogFactory.getLog(HibernateJpaConfiguration.class);

	private static final String JTA_PLATFORM = "hibernate.transaction.jta.platform";

	private static final String PROVIDER_DISABLES_AUTOCOMMIT = "hibernate.connection.provider_disables_autocommit";

	/**
	 * NoJtaPlatform implementations for various Hibernate versions.
	 */
	private static final String[] NO_JTA_PLATFORM_CLASSES = {
			"org.hibernate.engine.transaction.jta.platform.internal.NoJtaPlatform",
			"org.hibernate.service.jta.platform.internal.NoJtaPlatform" };

	private final HibernateProperties hibernateProperties;

	private final HibernateDefaultDdlAutoProvider defaultDdlAutoProvider;

	private DataSourcePoolMetadataProvider poolMetadataProvider;

	private final List<HibernatePropertiesCustomizer> hibernatePropertiesCustomizers;

	HibernateJpaConfiguration(DataSource dataSource, JpaProperties jpaProperties,
			ConfigurableListableBeanFactory beanFactory,
			ObjectProvider<JtaTransactionManager> jtaTransactionManager,
			ObjectProvider<TransactionManagerCustomizers> transactionManagerCustomizers,
			HibernateProperties hibernateProperties,
			ObjectProvider<Collection<DataSourcePoolMetadataProvider>> metadataProviders,
			ObjectProvider<SchemaManagementProvider> providers,
			ObjectProvider<PhysicalNamingStrategy> physicalNamingStrategy,
			ObjectProvider<ImplicitNamingStrategy> implicitNamingStrategy,
			ObjectProvider<HibernatePropertiesCustomizer> hibernatePropertiesCustomizers) {
		super(dataSource, jpaProperties, jtaTransactionManager,
				transactionManagerCustomizers);
		this.hibernateProperties = hibernateProperties;
		this.defaultDdlAutoProvider = new HibernateDefaultDdlAutoProvider(providers);
		this.poolMetadataProvider = new CompositeDataSourcePoolMetadataProvider(
				metadataProviders.getIfAvailable());
		this.hibernatePropertiesCustomizers = determineHibernatePropertiesCustomizers(
				physicalNamingStrategy.getIfAvailable(),
				implicitNamingStrategy.getIfAvailable(), beanFactory,
				hibernatePropertiesCustomizers.orderedStream()
						.collect(Collectors.toList()));
	}

	private List<HibernatePropertiesCustomizer> determineHibernatePropertiesCustomizers(
			PhysicalNamingStrategy physicalNamingStrategy,
			ImplicitNamingStrategy implicitNamingStrategy,
			ConfigurableListableBeanFactory beanFactory,
			List<HibernatePropertiesCustomizer> hibernatePropertiesCustomizers) {
		List<HibernatePropertiesCustomizer> customizers = new ArrayList<>();
		if (ClassUtils.isPresent(
				"org.hibernate.resource.beans.container.spi.BeanContainer",
				getClass().getClassLoader())) {
			customizers
					.add((properties) -> properties.put(AvailableSettings.BEAN_CONTAINER,
							new SpringBeanContainer(beanFactory)));
		}
		if (physicalNamingStrategy != null || implicitNamingStrategy != null) {
			customizers.add(new NamingStrategiesHibernatePropertiesCustomizer(
					physicalNamingStrategy, implicitNamingStrategy));
		}
		customizers.addAll(hibernatePropertiesCustomizers);
		return customizers;
	}

	@Override
	protected AbstractJpaVendorAdapter createJpaVendorAdapter() {
		return new HibernateJpaVendorAdapter();
	}

	@Override
	protected Map<String, Object> getVendorProperties() {
		Supplier<String> defaultDdlMode = () -> this.defaultDdlAutoProvider
				.getDefaultDdlAuto(getDataSource());
		return new LinkedHashMap<>(this.hibernateProperties.determineHibernateProperties(
				getProperties().getProperties(),
				new HibernateSettings().ddlAuto(defaultDdlMode)
						.hibernatePropertiesCustomizers(
								this.hibernatePropertiesCustomizers)));
	}

	@Override
	protected void customizeVendorProperties(Map<String, Object> vendorProperties) {
		super.customizeVendorProperties(vendorProperties);
		if (!vendorProperties.containsKey(JTA_PLATFORM)) {
			configureJtaPlatform(vendorProperties);
		}
		if (!vendorProperties.containsKey(PROVIDER_DISABLES_AUTOCOMMIT)) {
			configureProviderDisablesAutocommit(vendorProperties);
		}
	}

	private void configureJtaPlatform(Map<String, Object> vendorProperties)
			throws LinkageError {
		JtaTransactionManager jtaTransactionManager = getJtaTransactionManager();
		// Make sure Hibernate doesn't attempt to auto-detect a JTA platform
		if (jtaTransactionManager == null) {
			vendorProperties.put(JTA_PLATFORM, getNoJtaPlatformManager());
		}
		// As of Hibernate 5.2, Hibernate can fully integrate with the WebSphere
		// transaction manager on its own.
		else if (!runningOnWebSphere()) {
			configureSpringJtaPlatform(vendorProperties, jtaTransactionManager);
		}
	}

	private void configureProviderDisablesAutocommit(
			Map<String, Object> vendorProperties) {
		if (isDataSourceAutoCommitDisabled() && !isJta()) {
			vendorProperties.put(PROVIDER_DISABLES_AUTOCOMMIT, "true");
		}
	}

	private boolean isDataSourceAutoCommitDisabled() {
		DataSourcePoolMetadata poolMetadata = this.poolMetadataProvider
				.getDataSourcePoolMetadata(getDataSource());
		return poolMetadata != null
				&& Boolean.FALSE.equals(poolMetadata.getDefaultAutoCommit());
	}

	private boolean runningOnWebSphere() {
		return ClassUtils.isPresent(
				"com.ibm.websphere.jtaextensions.ExtendedJTATransaction",
				getClass().getClassLoader());
	}

	private void configureSpringJtaPlatform(Map<String, Object> vendorProperties,
			JtaTransactionManager jtaTransactionManager) {
		try {
			vendorProperties.put(JTA_PLATFORM,
					new SpringJtaPlatform(jtaTransactionManager));
		}
		catch (LinkageError ex) {
			// NoClassDefFoundError can happen if Hibernate 4.2 is used and some
			// containers (e.g. JBoss EAP 6) wrap it in the superclass LinkageError
			if (!isUsingJndi()) {
				throw new IllegalStateException("Unable to set Hibernate JTA "
						+ "platform, are you using the correct "
						+ "version of Hibernate?", ex);
			}
			// Assume that Hibernate will use JNDI
			if (logger.isDebugEnabled()) {
				logger.debug("Unable to set Hibernate JTA platform : " + ex.getMessage());
			}
		}
	}

	private boolean isUsingJndi() {
		try {
			return JndiLocatorDelegate.isDefaultJndiEnvironmentAvailable();
		}
		catch (Error ex) {
			return false;
		}
	}

	private Object getNoJtaPlatformManager() {
		for (String candidate : NO_JTA_PLATFORM_CLASSES) {
			try {
				return Class.forName(candidate).newInstance();
			}
			catch (Exception ex) {
				// Continue searching
			}
		}
		throw new IllegalStateException("No available JtaPlatform candidates amongst "
				+ Arrays.toString(NO_JTA_PLATFORM_CLASSES));
	}

	private static class NamingStrategiesHibernatePropertiesCustomizer
			implements HibernatePropertiesCustomizer {

		private final PhysicalNamingStrategy physicalNamingStrategy;

		private final ImplicitNamingStrategy implicitNamingStrategy;

		NamingStrategiesHibernatePropertiesCustomizer(
				PhysicalNamingStrategy physicalNamingStrategy,
				ImplicitNamingStrategy implicitNamingStrategy) {
			this.physicalNamingStrategy = physicalNamingStrategy;
			this.implicitNamingStrategy = implicitNamingStrategy;
		}

		@Override
		public void customize(Map<String, Object> hibernateProperties) {
			if (this.physicalNamingStrategy != null) {
				hibernateProperties.put("hibernate.physical_naming_strategy",
						this.physicalNamingStrategy);
			}
			if (this.implicitNamingStrategy != null) {
				hibernateProperties.put("hibernate.implicit_naming_strategy",
						this.implicitNamingStrategy);
			}
		}

	}

}

参考文章

• Spring Boot 自动配置 : HibernateJpaAutoConfiguration
• Spring Boot 配置 : JpaBaseConfiguration