Hibernate 升级到 5.2 - 创建会话工厂并替换 PersistentClass 以获取实体 class 属性
Hibernate upgrade to 5.2 - Session Factory creation and replacing PersistentClass for getting entity class properties
我目前正在将我的 Hibernate 版本升级到最新版本 5.2.10。我在 HibernateUtil 中替换了我的代码以创建 SessionFactory。
4.3.11.Final(上一个):
public class HibernateUtil {
private HibernateUtil() {}
private static SessionFactory sessionFactory;
private static Configuration configuration;
public static Configuration getConfiguration() {
return configuration;
}
private static SessionFactory buildSessionFactory() {
try {
if(sessionFactory == null) {
configuration = new Configuration();
configuration.configure("hibernate.cfg.xml");
ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()
.applySettings(configuration.getProperties()).build();
sessionFactory = configuration
.buildSessionFactory(serviceRegistry);
}
return sessionFactory;
}
catch (Throwable ex) {
throw new ExceptionInInitializerError(ex);
}
}
public static SessionFactory getSessionFactory() {
return buildSessionFactory();
}
public static Session getSession() {
Session hibernateSession = getSessionFactory().getCurrentSession();
return hibernateSession;
}
public static void shutdown() {
getSessionFactory().close();
}
}
5.2.10 决赛(新):
public class HibernateUtil {
private static StandardServiceRegistry registry;
private static SessionFactory sessionFactory;
public static SessionFactory getSessionFactory() {
return buildSessionFactory();
}
public static SessionFactory buildSessionFactory() {
if (sessionFactory == null) {
try {
registry = new StandardServiceRegistryBuilder().configure("hibernate.cfg.xml").build();
MetadataSources sources = new MetadataSources(registry);
Metadata metadata = sources.getMetadataBuilder().build();
sessionFactory = metadata.getSessionFactoryBuilder().build();
} catch (Exception e) {
e.printStackTrace();
shutdown();
}
}
return sessionFactory;
}
public static Session getSession() {
Session hibernateSession = getSessionFactory().getCurrentSession();
return hibernateSession;
}
public static void shutdown() {
if (registry != null) {
StandardServiceRegistryBuilder.destroy(registry);
}
}
}
现在我有一个方法可以通过将 DB table 名称作为字符串传递给我获取列名列表。我之前在 4.3.11.Final:
中是这样做的
public static List<String> getColumnNames(String tableName) {
List<String> columnList=null;
Map<String, ClassMetadata> map = HibernateUtil.getSessionFactory().getAllClassMetadata();
Iterator<Entry<String, ClassMetadata>> itr = map.entrySet().iterator();
while(itr.hasNext()){
ClassMetadata classMetaData = itr.next().getValue();
AbstractEntityPersister aep = (AbstractEntityPersister) classMetaData;
if(aep.getTableName().split("\.")[1].equalsIgnoreCase(tableName)){
columnList = new ArrayList<String>();
String[] propertyNames = classMetaData.getPropertyNames();
for(String property : propertyNames){
try {
PersistentClass persistentClass = HibernateUtil .getConfiguration().getClassMapping(classMetaData.getEntityName());
String clmName = ((Column) persistentClass.getProperty(property).getColumnIterator().next()).getName();
columnList.add(clmName);
} catch(NoSuchElementException e){
log.error("Element not found idenfied as : "+property);
} catch(Exception e){
log.error(e.getMessage());
}
}
break;
}
}
return columnList;
}
现在,升级后它显示方法 getAllClassMetadata 已弃用,并且在获取 PersistentClass 对象时遇到困难。我看到了一个类似的问题 但我无法确切地找出解决方案。我必须更改当前代码的哪一部分才能使我的 getColumnNames() 方法完全像以前一样工作。我参考了文档,它说使用 EntityManagerFactory.getMetamodel()
代替,但我找不到相同的 suitable 参考示例。我还必须为此更改 SessionFactory 创建机制吗?
首先,我们需要创建一个新的 MetadataExtractorIntegrator
class 来实现 Hibernate Integrator
:
public class MetadataExtractorIntegrator
implements org.hibernate.integrator.spi.Integrator {
public static final MetadataExtractorIntegrator INSTANCE =
new MetadataExtractorIntegrator();
private Database database;
@Override
public void integrate(
Metadata metadata,
SessionFactoryImplementor sessionFactory,
SessionFactoryServiceRegistry serviceRegistry) {
database = metadata.getDatabase();
}
@Override
public void disintegrate(
SessionFactoryImplementor sessionFactory,
SessionFactoryServiceRegistry serviceRegistry) {
}
public Database getDatabase() {
return database;
}
}
然后,我们只需配置 Hibernate 即可使用它。
如果您使用的是 Hibernate bootstrap 机制,那么您可以这样添加:
final BootstrapServiceRegistryBuilder bsrb = new BootstrapServiceRegistryBuilder();
bsrb.enableAutoClose();
Integrator integrator = integrator();
if (integrator != null) {
bsrb.applyIntegrator( integrator );
}
final BootstrapServiceRegistry bsr = bsrb.build();
final StandardServiceRegistryBuilder ssrb = new StandardServiceRegistryBuilder(bsr);
如果您bootstrap使用 JPA ping,那么您可以按如下方式进行:
protected EntityManagerFactory newEntityManagerFactory() {
PersistenceUnitInfo persistenceUnitInfo = persistenceUnitInfo(
getClass().getSimpleName()
);
Map<String, Object> configuration = new HashMap<>();
configuration.put("hibernate.integrator_provider",
(IntegratorProvider) () -> Collections.singletonList( MetadataExtractorIntegrator.INSTANCE )
);
EntityManagerFactoryBuilderImpl entityManagerFactoryBuilder = new EntityManagerFactoryBuilderImpl(
new PersistenceUnitInfoDescriptor(persistenceUnitInfo), configuration
);
return entityManagerFactoryBuilder.build();
}
现在,当运行进行以下测试时:
for(Namespace namespace : MetadataExtractorIntegrator.INSTANCE
.getDatabase()
.getNamespaces()) {
for( Table table : namespace.getTables()) {
LOGGER.info( "Table {} has the following columns: {}",
table,
StreamSupport.stream(
Spliterators.spliteratorUnknownSize(
table.getColumnIterator(),
Spliterator.ORDERED
),
false
)
.collect( Collectors.toList())
);
}
}
Hibernate 在日志中输出所有当前映射的表:
Table org.hibernate.mapping.Table(post) has the following columns: [
org.hibernate.mapping.Column(id),
org.hibernate.mapping.Column(title),
org.hibernate.mapping.Column(version)
]
Table org.hibernate.mapping.Table(post_comment) has the following columns: [
org.hibernate.mapping.Column(id),
org.hibernate.mapping.Column(review),
org.hibernate.mapping.Column(version),
org.hibernate.mapping.Column(post_id)
]
Table org.hibernate.mapping.Table(post_details) has the following columns: [
org.hibernate.mapping.Column(id),
org.hibernate.mapping.Column(created_by),
org.hibernate.mapping.Column(created_on),
org.hibernate.mapping.Column(version)
]
Table org.hibernate.mapping.Table(post_tag) has the following columns: [
org.hibernate.mapping.Column(post_id),
org.hibernate.mapping.Column(tag_id)
]
Table org.hibernate.mapping.Table(tag) has the following columns: [
org.hibernate.mapping.Column(id),
org.hibernate.mapping.Column(name),
org.hibernate.mapping.Column(version)
]
就是这样!
好吧,感谢 Vlad 的文章,我终于做到了。我在没有任何更改的情况下获取了集成器代码,并修改了我的 HibernateUtil
和 getColumns()
方法。所以这是我的代码:
SessionFactory 创建:
public class HibernateUtil {
private static final SessionFactory sessionFactory = buildSessionFactory();
public static SessionFactory getSessionFactory() {
return buildSessionFactory();
}
private static SessionFactory buildSessionFactory() {
final BootstrapServiceRegistry bootstrapServiceRegistry = new BootstrapServiceRegistryBuilder().enableAutoClose()
.applyIntegrator(MetadataExtractorIntegrator.INSTANCE).build();
final StandardServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder(bootstrapServiceRegistry).configure().build();
return new MetadataSources(serviceRegistry).buildMetadata().buildSessionFactory();
}
public static Session getSession() {
Session hibernateSession = getSessionFactory().getCurrentSession();
return hibernateSession;
}
public static void shutdown() {
getSessionFactory().close();
}
}
元数据提取器(获取列名):
public static List<String> getColumnNames(String tableName) {
List<String> columnList = new ArrayList<>();
for (Namespace namespace : MetadataExtractorIntegrator.INSTANCE.getDatabase().getNamespaces()) {
for (Table table : namespace.getTables()) {
if (table.getName().equalsIgnoreCase(lookupTableName)) {
Iterator<Column> iterator = table.getColumnIterator();
while (iterator.hasNext()) {
columnList.add(iterator.next().getName());
}
break;
}
}
if (!columnList.isEmpty())
break;
}
return columnList;
}
使用 hibernate 5 获取列名的更简单方法
final AbstractEntityPersister classMetadata = (AbstractEntityPersister) sessionFactory.getClassMetadata(clazz)
final String[] names = classMetadata.getPropertyColumnNames(property)
Hibernate - 5.4.30.Final - 2021 年 3 月 19 日发布
下面的代码有效并且未弃用:
MetamodelImplementor metaModelImpl = (MetamodelImplementor)session.getMetamodel();
Map<String, EntityPersister> entityPersisters = metaModelImpl.entityPersisters();
Collection<EntityPersister> val = entityPersisters.values();
for (EntityPersister ep : val) {
AbstractEntityPersister aep = (AbstractEntityPersister)ep;
System.out.println(aep.getTableName());
System.out.println(Arrays.toString(aep.getIdentifierColumnNames()));
for (String propName : aep.getPropertyNames()) {
System.out.println(propName);
System.out.println(Arrays.toString(aep.getPropertyColumnNames(propName)));
}
}
我目前正在将我的 Hibernate 版本升级到最新版本 5.2.10。我在 HibernateUtil 中替换了我的代码以创建 SessionFactory。
4.3.11.Final(上一个):
public class HibernateUtil {
private HibernateUtil() {}
private static SessionFactory sessionFactory;
private static Configuration configuration;
public static Configuration getConfiguration() {
return configuration;
}
private static SessionFactory buildSessionFactory() {
try {
if(sessionFactory == null) {
configuration = new Configuration();
configuration.configure("hibernate.cfg.xml");
ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()
.applySettings(configuration.getProperties()).build();
sessionFactory = configuration
.buildSessionFactory(serviceRegistry);
}
return sessionFactory;
}
catch (Throwable ex) {
throw new ExceptionInInitializerError(ex);
}
}
public static SessionFactory getSessionFactory() {
return buildSessionFactory();
}
public static Session getSession() {
Session hibernateSession = getSessionFactory().getCurrentSession();
return hibernateSession;
}
public static void shutdown() {
getSessionFactory().close();
}
}
5.2.10 决赛(新):
public class HibernateUtil {
private static StandardServiceRegistry registry;
private static SessionFactory sessionFactory;
public static SessionFactory getSessionFactory() {
return buildSessionFactory();
}
public static SessionFactory buildSessionFactory() {
if (sessionFactory == null) {
try {
registry = new StandardServiceRegistryBuilder().configure("hibernate.cfg.xml").build();
MetadataSources sources = new MetadataSources(registry);
Metadata metadata = sources.getMetadataBuilder().build();
sessionFactory = metadata.getSessionFactoryBuilder().build();
} catch (Exception e) {
e.printStackTrace();
shutdown();
}
}
return sessionFactory;
}
public static Session getSession() {
Session hibernateSession = getSessionFactory().getCurrentSession();
return hibernateSession;
}
public static void shutdown() {
if (registry != null) {
StandardServiceRegistryBuilder.destroy(registry);
}
}
}
现在我有一个方法可以通过将 DB table 名称作为字符串传递给我获取列名列表。我之前在 4.3.11.Final:
中是这样做的public static List<String> getColumnNames(String tableName) {
List<String> columnList=null;
Map<String, ClassMetadata> map = HibernateUtil.getSessionFactory().getAllClassMetadata();
Iterator<Entry<String, ClassMetadata>> itr = map.entrySet().iterator();
while(itr.hasNext()){
ClassMetadata classMetaData = itr.next().getValue();
AbstractEntityPersister aep = (AbstractEntityPersister) classMetaData;
if(aep.getTableName().split("\.")[1].equalsIgnoreCase(tableName)){
columnList = new ArrayList<String>();
String[] propertyNames = classMetaData.getPropertyNames();
for(String property : propertyNames){
try {
PersistentClass persistentClass = HibernateUtil .getConfiguration().getClassMapping(classMetaData.getEntityName());
String clmName = ((Column) persistentClass.getProperty(property).getColumnIterator().next()).getName();
columnList.add(clmName);
} catch(NoSuchElementException e){
log.error("Element not found idenfied as : "+property);
} catch(Exception e){
log.error(e.getMessage());
}
}
break;
}
}
return columnList;
}
现在,升级后它显示方法 getAllClassMetadata 已弃用,并且在获取 PersistentClass 对象时遇到困难。我看到了一个类似的问题 EntityManagerFactory.getMetamodel()
代替,但我找不到相同的 suitable 参考示例。我还必须为此更改 SessionFactory 创建机制吗?
首先,我们需要创建一个新的 MetadataExtractorIntegrator
class 来实现 Hibernate Integrator
:
public class MetadataExtractorIntegrator
implements org.hibernate.integrator.spi.Integrator {
public static final MetadataExtractorIntegrator INSTANCE =
new MetadataExtractorIntegrator();
private Database database;
@Override
public void integrate(
Metadata metadata,
SessionFactoryImplementor sessionFactory,
SessionFactoryServiceRegistry serviceRegistry) {
database = metadata.getDatabase();
}
@Override
public void disintegrate(
SessionFactoryImplementor sessionFactory,
SessionFactoryServiceRegistry serviceRegistry) {
}
public Database getDatabase() {
return database;
}
}
然后,我们只需配置 Hibernate 即可使用它。
如果您使用的是 Hibernate bootstrap 机制,那么您可以这样添加:
final BootstrapServiceRegistryBuilder bsrb = new BootstrapServiceRegistryBuilder();
bsrb.enableAutoClose();
Integrator integrator = integrator();
if (integrator != null) {
bsrb.applyIntegrator( integrator );
}
final BootstrapServiceRegistry bsr = bsrb.build();
final StandardServiceRegistryBuilder ssrb = new StandardServiceRegistryBuilder(bsr);
如果您bootstrap使用 JPA ping,那么您可以按如下方式进行:
protected EntityManagerFactory newEntityManagerFactory() {
PersistenceUnitInfo persistenceUnitInfo = persistenceUnitInfo(
getClass().getSimpleName()
);
Map<String, Object> configuration = new HashMap<>();
configuration.put("hibernate.integrator_provider",
(IntegratorProvider) () -> Collections.singletonList( MetadataExtractorIntegrator.INSTANCE )
);
EntityManagerFactoryBuilderImpl entityManagerFactoryBuilder = new EntityManagerFactoryBuilderImpl(
new PersistenceUnitInfoDescriptor(persistenceUnitInfo), configuration
);
return entityManagerFactoryBuilder.build();
}
现在,当运行进行以下测试时:
for(Namespace namespace : MetadataExtractorIntegrator.INSTANCE
.getDatabase()
.getNamespaces()) {
for( Table table : namespace.getTables()) {
LOGGER.info( "Table {} has the following columns: {}",
table,
StreamSupport.stream(
Spliterators.spliteratorUnknownSize(
table.getColumnIterator(),
Spliterator.ORDERED
),
false
)
.collect( Collectors.toList())
);
}
}
Hibernate 在日志中输出所有当前映射的表:
Table org.hibernate.mapping.Table(post) has the following columns: [
org.hibernate.mapping.Column(id),
org.hibernate.mapping.Column(title),
org.hibernate.mapping.Column(version)
]
Table org.hibernate.mapping.Table(post_comment) has the following columns: [
org.hibernate.mapping.Column(id),
org.hibernate.mapping.Column(review),
org.hibernate.mapping.Column(version),
org.hibernate.mapping.Column(post_id)
]
Table org.hibernate.mapping.Table(post_details) has the following columns: [
org.hibernate.mapping.Column(id),
org.hibernate.mapping.Column(created_by),
org.hibernate.mapping.Column(created_on),
org.hibernate.mapping.Column(version)
]
Table org.hibernate.mapping.Table(post_tag) has the following columns: [
org.hibernate.mapping.Column(post_id),
org.hibernate.mapping.Column(tag_id)
]
Table org.hibernate.mapping.Table(tag) has the following columns: [
org.hibernate.mapping.Column(id),
org.hibernate.mapping.Column(name),
org.hibernate.mapping.Column(version)
]
就是这样!
好吧,感谢 Vlad 的文章,我终于做到了。我在没有任何更改的情况下获取了集成器代码,并修改了我的 HibernateUtil
和 getColumns()
方法。所以这是我的代码:
SessionFactory 创建:
public class HibernateUtil {
private static final SessionFactory sessionFactory = buildSessionFactory();
public static SessionFactory getSessionFactory() {
return buildSessionFactory();
}
private static SessionFactory buildSessionFactory() {
final BootstrapServiceRegistry bootstrapServiceRegistry = new BootstrapServiceRegistryBuilder().enableAutoClose()
.applyIntegrator(MetadataExtractorIntegrator.INSTANCE).build();
final StandardServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder(bootstrapServiceRegistry).configure().build();
return new MetadataSources(serviceRegistry).buildMetadata().buildSessionFactory();
}
public static Session getSession() {
Session hibernateSession = getSessionFactory().getCurrentSession();
return hibernateSession;
}
public static void shutdown() {
getSessionFactory().close();
}
}
元数据提取器(获取列名):
public static List<String> getColumnNames(String tableName) {
List<String> columnList = new ArrayList<>();
for (Namespace namespace : MetadataExtractorIntegrator.INSTANCE.getDatabase().getNamespaces()) {
for (Table table : namespace.getTables()) {
if (table.getName().equalsIgnoreCase(lookupTableName)) {
Iterator<Column> iterator = table.getColumnIterator();
while (iterator.hasNext()) {
columnList.add(iterator.next().getName());
}
break;
}
}
if (!columnList.isEmpty())
break;
}
return columnList;
}
使用 hibernate 5 获取列名的更简单方法
final AbstractEntityPersister classMetadata = (AbstractEntityPersister) sessionFactory.getClassMetadata(clazz)
final String[] names = classMetadata.getPropertyColumnNames(property)
Hibernate - 5.4.30.Final - 2021 年 3 月 19 日发布
下面的代码有效并且未弃用:
MetamodelImplementor metaModelImpl = (MetamodelImplementor)session.getMetamodel();
Map<String, EntityPersister> entityPersisters = metaModelImpl.entityPersisters();
Collection<EntityPersister> val = entityPersisters.values();
for (EntityPersister ep : val) {
AbstractEntityPersister aep = (AbstractEntityPersister)ep;
System.out.println(aep.getTableName());
System.out.println(Arrays.toString(aep.getIdentifierColumnNames()));
for (String propName : aep.getPropertyNames()) {
System.out.println(propName);
System.out.println(Arrays.toString(aep.getPropertyColumnNames(propName)));
}
}