for some reason the database (ugly!) that I should use contains all the tables twice; every table are duplicated into these modes: DB1_<table> and DB2_<table>.
The structures of these databases are the same!
The application that I am realizing uses Spring + Hibernate and should permit to the users to change the database on runtime; this mean that a user can start the application using database DB1 and after some minutes change to DB2, return to DB1 and so on.
I have tried to extend DefaultNamingStrategy for every databases:
// I have create also DB2
public class DB1 extends DefaultNamingStrategy {
private static final long serialVersionUID = 676544180324515651L;
#Override
public String tableName(String tableName) {
return "DB1_" + tableName;
}
}
and set the naming strategy through the property hibernate.ejb.naming_strategy of jpa dinamically but for a reason that I can't understand I can change the naming strategy only once, and all next callings trown an Exception.
Someone know why?
Configuration of entityManagerFactory:
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="packagesToScan" value="it.perfectquiz.entity" />
<property name="persistenceProviderClass" value="org.hibernate.jpa.HibernatePersistenceProvider" />
<property name="jpaProperties">
<props>
<prop key="hibernate.dialect">${hibernate.dialect}</prop>
<prop key="hibernate.format_sql">${hibernate.format_sql}</prop>
<prop key="hibernate.show_sql">${hibernate.show_sql}</prop>
</props>
</property>
</bean>
How I try to change naming strategy:
XmlWebApplicationContext context = (XmlWebApplicationContext) ContextLoader.getCurrentWebApplicationContext();
DefaultListableBeanFactory beanFactory = (DefaultListableBeanFactory) context.getBeanFactory();
GenericBeanDefinition entityManager = (GenericBeanDefinition) beanFactory.getBeanDefinition("entityManagerFactory");
ManagedProperties jpaProperties = (ManagedProperties) entityManager.getPropertyValues().get("jpaProperties");
TypedStringValue namingStrategy = (TypedStringValue) jpaProperties.get(new TypedStringValue("hibernate.ejb.naming_strategy"));
// only for test!
String newNaming;
if (namingStrategy.getValue().equals(DB1.class.getCanonicalName()))
newNaming = DB2.class.getCanonicalName();
else
newNaming = DB1.class.getCanonicalName();
// only for test!
namingStrategy.setValue(newNaming);
beanFactory.registerBeanDefinition("entityManagerFactory", entityManager);
Thanks,
Regards
Related
I am working on a Spring application which has a persistence unit configured in the application-context.xml. I need to add an additional package in in order to use new entities.
Even though this part of the persistence.xml file looks like below, my entities from the additional package are not seen by the application and I get an exception saying that the entity is unknown.
<bean id="transactionManager_students" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactoryStudents" />
<qualifier value="clientTransaction" />
</bean>
<bean id="entityManagerFactoryStudents"
class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="datasource_College" />
<property name="jpaVendorAdapter" ref="hibernateJpaVendorAdapter" />
<property name="packagesToScan">
<list>
<value>com.load.model</value>
<value>com.students.entity</value>
</list>
</property>
<property name="persistenceUnitName" value="unit_stud" />
<property name="jpaProperties">
<props>
<prop key="hibernate.generate_statistics">true</prop>
<prop key="hibernate.cache.use_query_cache">false</prop>
<prop key="hibernate.cache.use_second_level_cache">false</prop>
<prop key="hibernate.hbm2ddl.auto">none</prop>
<prop key="hibernate.show_sql">false</prop>
</props>
</property>
</bean>
I also have to mention that I annotated the entities with #Entity and in the class where I am operating on the entities I have this ( the row with em.persist(student) is giving me the error )
#PersistenceContext(unitName = "unit_stud")
public EntityManager em;
public Student student;
#Transactional(value = "clientTransaction", propagation = Propagation.REQUIRED)
public long persistStudentObject() {
long studentId = 0;
try
{
logger.debug("Start Persisting...");
em.persist(student);
// unique ID
studentId = student.getId();
logger.debug("Persisting OK...");
}
catch (PersistenceException persistenceException)
{
logger.error("PersistenceException occur", persistenceException);
}
}
return studentId ;
}
The entity:
package com.students.entity;
#Entity
#Table(name = "STUDENTS", schema = "DEMO", catalog = "")
public class Student{
private long id;
private String firstname;
private String name;
private String streetnumber;
private String zipcodecity;
Can anyone help me? I do not know what to do in order to make my entities visible.
I'm using Hibernate 4 to write data to an H2 embedded in-memory database and there seems to be a problem with transactions. The application already uses Oracle and H2 has been added with a separate DataSource, SessionFactory, and TransactionManager. The original TransactionManager is marked as default and the H2 TransactionManager has the qualifier memTransactions
The following code - specifically the load function - correctly populates the memEvents variable at the end with the written data.
#Repository
#Transactional(transactionManager = "memTransactions")
public class EventMemDaoHibernate implements EventMemDao {
#Autowired
#Qualifier(value = "memSessionFactory")
private SessionFactory memSessionFactory;
#Override
public List<EventMem> getEvents() {
return memSessionFactory.getCurrentSession().createCriteria(EventMem.class).list();
}
#Override
public void load(List<Event> allEvents) {
Session session = memSessionFactory.getCurrentSession();
for (Event e : allEvents) {
EventMem memEvent = new EventMem(e);
session.save(memEvent);
}
List<EventMem> memEvents = getEvents(); // correct
}
}
However the following code produces an empty memEvents list
#Autowired
private EventMemDao eventMemDao;
List<Event> allEvents = eventDao.getAllEvents();
eventMemDao.load(allEvents); // calls the load function shown above
List<EventMem> memEvents = eventMemDao.getEvents(); // empty
I assume this is related to transaction management (e.g.: data is not auto-committed after the call to .save()). However when I tried explicitly beginning and committing a transaction within EventMemDaoHibernate#load, I receive this error:
nested transactions not supported
So, from what I can tell the TransactionManager is working.
My TransactionManager and related bean definitions are shown below.
<bean
id="memTransactionManager"
class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="memSessionFactory" />
<qualifier value="memTransactions"/>
</bean>
<bean id="hDataSource" class="org.h2.jdbcx.JdbcDataSource">
<property name="url" value="jdbc:h2:mem:db1;DB_CLOSE_DELAY=-1;INIT=RUNSCRIPT FROM 'classpath:scripts/init-h2.sql'" />
<property name="user" value="sa" />
<property name="password" value="" />
</bean>
<bean
id="memSessionFactory"
class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="hDataSource" />
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.H2Dialect</prop>
</props>
</property>
</bean>
This was due to my configuration error (of course). I didn't fully grasp that the connection URL was evaluated every time a session was opened against H2 and that means init-h2.sql was executed repeatedly. init-h2.sql included a truncate followed by an insert so it was dropping and recreating data every time Hibernate opened a session.
I am performing retrieval operation to get list of students from database. But I am getting 'empty' data from database. Used HibernateTemplate in
Spring with Hibernate integration,
domain class:-
#Entity
#Table(name="student")
public class StdBO {
#Id
private int sno;
private String sname,sadd;
//setters and getters
}
How can I use HibernateCallBack() interface for search operation? This is my first time that integrating spring with hibernate, is the below way correct? I tried many ways to perform search operations using HibernateTemplate but failing to get the details
DAO
#Repository
public class StdDAO {
private HibernateTemplate ht;
public void setHt(HibernateTemplate ht) {
this.ht = ht;
}
public List<StdBO> select(){
List<StdBO> list = ht.executeFind(new HibernateCallback() {
public Object doInHibernate(Session ses)
throws HibernateException, SQLException {
Criteria criteria=ses.createCriteria(StdBO.class);
System.out.println("before printing sutdents");
List<StdBO> bos = criteria.list();
System.out.println("students are"+bos);//here getting empty list
return bos;
}
});
return list;
}
xml
<bean id="sessionFactory"
class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
<property name="dataSource" ref="myDataSource" />
<property name="annotatedClasses">
<list>
<value>com.nt.dao.StdDAO</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.HSQLDialect</prop>
<prop key="hibernate.current_session_context_class">thread</prop>
</props>
</property>
</bean>
<bean id="template" class="org.springframework.orm.hibernate3.HibernateTemplate">
<property name="sessionFactory" ref="sessionFactory"></property>
</bean>
<bean id="dao" class="com.nt.dao.StdDAO">
<property name="ht" ref="template" />
</bean>
You need begin (and commit) a transaction to query data. You can do it manually by session.beginTransaction() or using #Transactional annotation. For using #Transactional annotation you will need to do some additional spring configuration:
Hibernate Transaction Annotation Configuration.
I am implementing a unit test using the H2 embedded database. When I insert an entry in a table, I am able to retrieve the entry using a native SQL query, but not with an HQL query. A find by the primary key also works through the JPA EntityManager interface. I am using Hibernate as the persistence provider.
Configuration:
<bean id="hibernateJpaVendorAdapter"
class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"
p:showSql="true" p:generateDdl="false" p:databasePlatform="org.hibernate.dialect.H2Dialect" />
<bean id="entityManagerFactory"
class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"
p:dataSource-ref="dataSource" p:jpaVendorAdapter-ref="hibernateJpaVendorAdapter"
p:persistenceUnitName="AMgSAdapter" p:packagesToScan="com.hcsc.amgs.adapter.domaindto">
<property name="jpaProperties">
<props>
<prop key="hibernate.hbm2ddl.auto">create</prop>
</props>
</property>
<property name="jpaPropertyMap">
<map>
<entry key="hibernate.ejb.interceptor" value="com.hcsc.amgs.adapter.dao.hibernate.interceptor.AuditableFieldInterceptor" />
</map>
</property>
</bean>
Test Case:
#Test
#Transactional(value="transactionManager",propagation = Propagation.REQUIRED)
public void getVasPolicyMatchesTest() {
Application application = TestDataCreationUtil.createApplication();
entityManager.persist(application.getX834EnrollmentApplicationTransaction());
entityManager.persist(application);
List<Application> matches = new ArrayList<Application>();
Query q = simpleQueryHQL();
matches= q.getResultList();
Application findApp = entityManager.find(Application.class, application.getId()); // this works
Assert.assertTrue(matches.size() > 0);
}
private Query simpleQueryHQL() {
return entityManager.createQuery("Select app From Application app", Application.class);
}
private Query simpleQuerySQL() {
return entityManager.createNativeQuery("Select * from Application", Application.class);
}
No exceptions are thrown, the test case fails for simpleQueryHQL() and passes for simpleQuerySQL()
We have a scenario where in the catalog/schema combination is different for the entity classes inside certain package from the default one used by all others. I am trying to set Catalog and Schema on #Table annotation using PersistenceUnitPostProcessors callback at runtime using javaassist as below.
The issue: The added member values on javaassist annotation are NOT getting reflected on to the actual class associated with it. Please help me in finding the wrong lines of code; OR if there are other ways to achieve this, more than happy to know.
Note: I do not want to create a separate EntityManagerFactory for each catalog/schema combination - it is not really required in our case as the datasource is same.
related content in spring context :
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
<tx:annotation-driven />
<bean name="jpaDialect" class="org.springframework.orm.jpa.vendor.HibernateJpaDialect" />
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="persistenceUnitName" value="mainUnit" />
<property name="packagesToScan" value="com.mycompany.lob.domain" />
<property name="jpaVendorAdapter">
<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter" />
</property>
<property name="persistenceUnitPostProcessors">
<list>
<bean class="com.mycompany.lob.jpa.CustomPersistenceUnitPostProcessor"/>
</list>
</property>
<property name="jpaProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.SqlmxDialect</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.format_sql">true</prop>
<prop key="hibernate.jdbc.batch_size">100</prop>
<prop key="hibernate.order_inserts">true</prop>
<prop key="hibernate.cache.use_second_level_cache">true</prop>
<prop key="hibernate.connection.autocommit">true</prop>
<prop key="hibernate.default_schema">DEFAULT_SCHEMA</prop>
<prop key="hibernate.default_catalog">DEFAULT_CATALOG</prop>
</props>
</property>
</bean>
PersistenceUnitPostProcessors callback :
public class CustomPersistenceUnitPostProcessor implements PersistenceUnitPostProcessor {
#Value("${user.schema}")
private String userSchema;
#Value("${user.catalog}")
private String userCatalog;
private static final Logger LOGGER = LoggerFactory.getLogger(CustomPersistenceUnitPostProcessor.class);
#SuppressWarnings("unchecked")
#Override
public void postProcessPersistenceUnitInfo(MutablePersistenceUnitInfo pui) {
LOGGER.info("MutablePersistenceUnitInfo : {} ",pui);
List<String> jpadomains = pui.getManagedClassNames();
for (Iterator<?> iterator = jpadomains.iterator(); iterator.hasNext();) {
String clazzName = (String) iterator.next();
if(clazzName.startsWith("com.mycompany.lob.domain.user")){
try {
//modify annotation attributes using JavaAssist
ClassPool pool = ClassPool.getDefault();
CtClass ctClass = pool.get(clazzName);
ClassFile classFile = ctClass.getClassFile();
ConstPool constPool = classFile.getConstPool();
AnnotationsAttribute annotationsAttribute = (AnnotationsAttribute)classFile.getAttribute(AnnotationsAttribute.visibleTag);
if(annotationsAttribute!=null){
//Get hold of #Table annotation
Annotation tableAnnotation = annotationsAttribute.getAnnotation("javax.persistence.Table");
if(tableAnnotation!=null){
tableAnnotation.addMemberValue("catalog", new StringMemberValue(userCatalog, constPool));
tableAnnotation.addMemberValue("schema", new StringMemberValue(userSchema, constPool));
annotationsAttribute.addAnnotation(tableAnnotation);
LOGGER.debug("Schema-Table : {} - {} ", ((StringMemberValue)tableAnnotation.getMemberValue("schema")).getValue(),
((StringMemberValue)tableAnnotation.getMemberValue("name")).getValue() );
//write the file back
ctClass.writeFile();
}
}
} catch (Exception e) {
LOGGER.error("Schema/Catalog could not be altered for {} ",clazzName);
}
}
}
}
}
Simple answer:
19. Multitenancy
Complex catalog mapping:
interface PhysicalNamingStrategy in Hibernate v5 is helpful.
public interface PhysicalNamingStrategy {
public Identifier toPhysicalCatalogName(Identifier name, JdbcEnvironment jdbcEnvironment);
public Identifier toPhysicalSchemaName(Identifier name, JdbcEnvironment jdbcEnvironment);
....
}
Check the Example 2. Example PhysicalNamingStrategy implementation in Hibernate 5 User Guide and how to config it