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java - Hibernate,在一个事务中修改多个表的正确方法

转载 作者:太空宇宙 更新时间:2023-11-04 10:38:19 25 4
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对于一个使用 Hibernate 的项目,我们有一个 DAO 每表模式。在每个 DAO 调用中,我们创建一个事务并在执行完成后提交。

现在,我们需要在同一事务中更新两个表。这种情况很常见,我们需要发出销售支票,然后减少库存中销售的元素数量。当然,这一切都必须在同一个事务中完成。

所以,我的问题是,这是在一个事务中修改多个表的正确方法。这是我们 DAO 之一的示例。正如您所看到的,每个 DAO 仅用于处理一张表。

我们尚未实现计费 DAO 或库存 DAO。我们想知道哪种方法是满足我们需求的正确方法。任何帮助都会很棒。

@Service
public class StoreDaoImplementation implements StoreDao {

// We are gonna use a session-per-request pattern, for each data access object (dao).
// In order to use it, we need an session factory that will provide us with sessions for each request.
private SessionFactory factory;

public StoreDaoImplementation() {
try{
factory = new Configuration().configure().buildSessionFactory();
}catch(Exception e){
e.printStackTrace();
}
}

/**
* {@inheritDoc}
*/
@Override
public Tienda findById(String storeId) {
Session session = factory.getCurrentSession();
Transaction tx = session.beginTransaction();
try {
return session.get(Tienda.class, storeId);
} catch (Exception e) {
return null;
} finally {
tx.commit();
}
}

/**
* {@inheritDoc}
*/
@Override
public void insert(Tienda tienda) throws Exception {
Session session = factory.getCurrentSession();
Transaction tx = session.beginTransaction();
session.persist(tienda);
tx.commit();
}

/**
* {@inheritDoc}
*/
@Override
public void delete(Tienda tienda) throws Exception {
Session session = factory.getCurrentSession();
Transaction tx = session.beginTransaction();
session.delete(tienda);
tx.commit();
}

/**
* {@inheritDoc}
*/
@Override
public void update(Tienda tienda) throws Exception {
Session session = factory.getCurrentSession();
Transaction tx = session.beginTransaction();
session.merge(tienda);
tx.commit();
}

/**
* {@inheritDoc}
*/
@Override
public void updateSupervisor(List<String> storeIds, String supervisorId) throws Exception {
Session session = factory.getCurrentSession();
Transaction tx = session.beginTransaction();
Query query = session.createQuery("UPDATE Tienda SET supervisor.idEmpleadoPk = :supervisorId WHERE idTiendaPk IN (:storeIds)");
query.setParameter("supervisorId", supervisorId);
query.setParameter("storeIds", storeIds);
query.executeUpdate();
tx.commit();
}

/**
* {@inheritDoc}
*/
@Override
public List<Tienda> getAllStores(Integer offset,
Integer rowNumber,
String franchise,
String country,
Boolean state,
String storeName,
Integer orderBy,
Integer orderType) {
// Always use getCurrentSession, instead of openSession.
// Only in very odd cases, should the latter be used, then we must remember to close our session.
// For more information, read the following docs.
// http://docs.jboss.org/hibernate/core/3.3/reference/en/html/transactions.html#transactions-basics-uow
Session session = factory.getCurrentSession();
// All hibernate transactions must be executed in an active transaction.
Transaction tx = session.beginTransaction();
try {
setSessionFilter(session, franchise, country, state, storeName);
// NOTE: In this query I am using join fetch. This is due a Hibernate bug, that won't allow
// setting the fetch type in the mapping file. What this does, is that instead of doing multiple selects
// for each join, it just simply does a big join in the main query.
// Much faster if you are working with a remote server.
String hql = "from Tienda T join fetch T.supervisor join fetch T.franquiciaFK join fetch T.pais";
switch ((orderBy != null) ? orderBy : 4) {
case 0:
hql += " order by T.franquiciaFK.franquiciaPk";
break;
case 1:
hql += " order by T.pais.paisPk";
break;
case 2:
hql += " order by T.provincia";
break;
case 3:
hql += " order by T.supervisor.idEmpleadoPk";
break;
default:
hql += " order by T.franquiciaFK.orden";
break;
}
switch ((orderType != null) ? orderType : 0) {
case 0:
hql += " asc";
break;
case 1:
hql += " desc";
break;
}
Query query = session.createQuery(hql);
query.setFirstResult(offset);
query.setMaxResults(rowNumber-1);
return query.list();
} catch (Exception e) {
return null;
} finally {
tx.commit();
}
}

/**
* {@inheritDoc}
*/
@Override
public List<Tienda> getStoresBySupervisor(String supervisorId) {
Session session = factory.getCurrentSession();
Transaction tx = session.beginTransaction();
try {
// NOTE: In this query I am using join fetch. This is due a Hibernate bug, that won't allow
// setting the fetch type in the mapping file. What this does, is that instead of doing multiple selects
// for each join, it just simply does a big join in the main query.
// Much faster if you are working with a remote server.
Query query = session.createQuery("from Tienda T join fetch T.supervisor join fetch T.franquiciaFK join fetch T.pais where T.supervisor.idEmpleadoPk = :supervisorId");
query.setParameter("supervisorId", supervisorId);
return query.list();
} catch (Exception e) {
return null;
} finally {
tx.commit();
}
}

/**
* {@inheritDoc}
*/
@Override
public Integer countAllStores(String franchise, String country, Boolean state, String storeName) {
Session session = factory.getCurrentSession();
Transaction tx = session.beginTransaction();
try {
// Check that the filters are not null.
setSessionFilter(session, franchise, country, state, storeName);
Query query = session.createQuery("select count(*) from Tienda");
return ((Long) query.iterate().next()).intValue();
} catch (Exception e) {
return null;
} finally {
tx.commit();
}
}

/**
* Given that we already know the all filters we can use in our stores' queries,
* we can make a method to configure them.
* @param session Actual session that will query the DB.
* @param franchise Franchise filter. Only returns those store of the specified franchise.
* @param country Country filter. Only returns those store of the specified country.
* @param state State filter. Only returns those stores of the specified state.
*/
private void setSessionFilter(Session session, String franchise, String country, Boolean state, String name) {
if(franchise != null && !franchise.isEmpty()) {
session.enableFilter("storeFranchiseFilter").setParameter("franchiseFilter", franchise);
}
if(country != null && !country.isEmpty()) {
session.enableFilter("storeCountryFilter").setParameter("countryFilter", country);
}
if(state != null) {
session.enableFilter("storeStateFilter").setParameter("stateFilter", state);
}
if(name != null && !name.isEmpty()) {
session.enableFilter("storeNameFilter").setParameter("nameFilter", "%"+name+"%");
}
}
}

最佳答案

您可以使用Transactional注释,它提供了更多控制,例如异常回滚以及处理多个事务。

public interface BillingService {

public BillingDAO getBalance();

}

@Service(value = "billingService")
@Transactional("transactionManager")
public class BillingServiceImpl implements BillingService {

@Autowired
private SessionFactory sessionFactory;

@Override
// Transactional // you can have method level transaction manager, which can be different from one method to another
public BillingDAO getBalance(long id) {
return sessionFactory.getCurrentSession().get(BillingDAO.class, id);
}

}

public interface StockService {

public StockDAO getStock();

}

@Service(value = "stockService")
@Transactional("transactionManager")
public class StockServiceImpl implements StockService {

@Autowired
private SessionFactory sessionFactory;

@Autowired
private BillingService billingService;

@Override
// Transactional
public StockDAO getStock(long id) {

// if you want to use billing related changes, use billing server which is autowired
BillingDAO billingDAO = billingService.getBalance(id);

return sessionFactory.getCurrentSession().get(StockDAO.class, billingDAO.getStockId());
}

}

@Configuration
@EnableTransactionManagement
public class DatabaseConfig {

@Autowired
private ApplicationContext appContext;

@Autowired
private ApplicationProperties applicationProperties;

@Bean
public HikariDataSource getDataSource() {
HikariDataSource dataSource = new HikariDataSource();

dataSource
.setDataSourceClassName(applicationProperties.getHibernateDatasource());
dataSource.addDataSourceProperty("databaseName", applicationProperties.getRdbmsDatabase());
dataSource.addDataSourceProperty("portNumber", applicationProperties.getRdbmsPort());
dataSource.addDataSourceProperty("serverName", applicationProperties.getRdbmsServer());
dataSource.addDataSourceProperty("user", applicationProperties.getRdbmsUser());
dataSource.addDataSourceProperty("password", applicationProperties.getRdbmsPassword());

return dataSource;
}

@Bean("transactionManager")
public HibernateTransactionManager transactionManager() {
HibernateTransactionManager manager = new HibernateTransactionManager();
manager.setSessionFactory(hibernate5SessionFactoryBean().getObject());
return manager;
}

@Bean(name = "sessionFactory")
public LocalSessionFactoryBean hibernate5SessionFactoryBean() {
LocalSessionFactoryBean localSessionFactoryBean = new LocalSessionFactoryBean();
localSessionFactoryBean.setDataSource(appContext
.getBean(HikariDataSource.class));
localSessionFactoryBean.setAnnotatedClasses(BillingDAO.class);

Properties properties = new Properties();

// properties.put("hibernate.current_session_context_class","thread");
// // because I am using Spring, it will take care of session context
/*
*
* Spring will by default set its own CurrentSessionContext
* implementation (the SpringSessionContext), however if you set it
* yourself this will not be the case. Basically breaking proper
* transaction integration.
*
* Ref:
* https://stackoverflow.com/questions/18832889/spring-transactions-and-hibernate-current-session-context-class
*/
properties.put("hibernate.dialect",
applicationProperties.getHibernateDialect());

properties.put("hibernate.hbm2ddl.auto", applicationProperties.getHibernateHbm2ddlAuto());
properties.put("hibernate.show_sql", applicationProperties.getShowSql());
// properties.put("hibernate.hbm2ddl.import_files",
// "/resource/default_data.sql"); // this will execute only
// when hbm2ddl.auto is set to "create" or "create-drop"
// properties.put("connection.autocommit", "true");

localSessionFactoryBean.setHibernateProperties(properties);
return localSessionFactoryBean;
}
}

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关于java - Hibernate,在一个事务中修改多个表的正确方法,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/49266852/

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