Возникают ситуации, когда entities находятся в неожиданном для Spring месте, и он не может их найти и объяснить hibernate где же их искать. Поэтому, что бы не указывать в файле persistance.xml все используемые entity, можно научить Spring искать их в заданном пакете.
Для этого необходимо создать свой bean, в котором указать пакет с enities:
<bean id="entitiesScanner" class="org.myapp.utils.EntitiesScanner">
<property name="packagesToScan">
<list>
<value>org.some.greate.package</value>
</list>
</property>
</bean>
А в bean LocalContainerEntityManagerFactoryBean добавить следующий аргумент:
<property name="persistenceUnitPostProcessors">
<list>
<ref bean="entitiesScanner"/>
</list>
</property>
Ну и создать класс собственно EntitiesScanner:
import org.hibernate.MappingException;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;
import org.springframework.core.type.classreading.CachingMetadataReaderFactory;
import org.springframework.core.type.classreading.MetadataReader;
import org.springframework.core.type.classreading.MetadataReaderFactory;
import org.springframework.core.type.filter.AnnotationTypeFilter;
import org.springframework.core.type.filter.TypeFilter;
import org.springframework.orm.jpa.persistenceunit.MutablePersistenceUnitInfo;
import org.springframework.orm.jpa.persistenceunit.PersistenceUnitPostProcessor;
import org.springframework.util.ClassUtils;
import javax.persistence.Embeddable;
import javax.persistence.Entity;
import javax.persistence.MappedSuperclass;
import java.io.IOException;
import java.util.HashSet;
import java.util.Set;
public class EntitiesScanner implements ApplicationContextAware, PersistenceUnitPostProcessor {
private static final String RESOURCE_PATTERN = "**/*.class";
private ApplicationContext applicationContext;
private String[] packagesToScan;
private ResourcePatternResolver resourcePatternResolver = new PathMatchingResourcePatternResolver();
private TypeFilter[] entityTypeFilters = new TypeFilter[]{
new AnnotationTypeFilter(Entity.class, false),
new AnnotationTypeFilter(Embeddable.class, false),
new AnnotationTypeFilter(MappedSuperclass.class, false)};
@Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
this.applicationContext = applicationContext;
}
@Override
public void postProcessPersistenceUnitInfo(MutablePersistenceUnitInfo pui) {
String[] entities = scanPackages();
for (String entity : entities) {
pui.addManagedClassName(entity);
}
}
/**
* Set whether to use Spring-based scanning for entity classes in the
* classpath instead of listing annotated classes explicitly.
* <p/>
* <p/>
* <p/>
* Default is none. Specify packages to search for autodetection of your
* entity classes in the classpath. This is analogous to
* <p/>
* Spring's component-scan feature
* (org.springframework.context.annotation.ClassPathBeanDefinitionScanner}).
*/
public void setPackagesToScan(String[] packagesToScan) {
this.packagesToScan = packagesToScan;
}
/**
* Perform Spring-based scanning for entity classes.
*
* @see #setPackagesToScan
*/
protected String[] scanPackages() {
Set<String> entities = new HashSet<String>();
if (this.packagesToScan != null) {
try {
for (String pkg : this.packagesToScan) {
String pattern = ResourcePatternResolver.CLASSPATH_ALL_URL_PREFIX
+ ClassUtils.convertClassNameToResourcePath(pkg) + RESOURCE_PATTERN;
Resource[] resources = this.resourcePatternResolver.getResources(pattern);
MetadataReaderFactory readerFactory = new CachingMetadataReaderFactory(this.resourcePatternResolver);
for (Resource resource : resources) {
if (resource.isReadable()) {
MetadataReader reader = readerFactory.getMetadataReader(resource);
String className = reader.getClassMetadata().getClassName();
if (matchesFilter(reader, readerFactory)) {
entities.add(className);
}
}
}
}
} catch (IOException ex) {
throw new MappingException("Failed to scan classpath for unlisted classes", ex);
}
}
return entities.toArray(new String[entities.size()]);
}
/**
* Check whether any of the configured entity type filters matches the
* current class descriptor contained in the metadata
* <p/>
* reader.
*/
private boolean matchesFilter(MetadataReader reader, MetadataReaderFactory readerFactory) throws IOException {
if (this.entityTypeFilters != null) {
for (TypeFilter filter : this.entityTypeFilters) {
if (filter.match(reader, readerFactory)) {
return true;
}
}
}
return false;
}
}
via
Spring, JPA, Hibernate Best Practices and Tips
Но если вы используете spring 3.1.1, то достаточно такого конфига:
<bean id="myEmf" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="persistenceProviderClass"
value="org.hibernate.ejb.HibernatePersistence"/>
<property name="jpaVendorAdapter">
<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"/>
</property>
<property name="jpaProperties">
<props>
<prop key="hibernate.connection.datasource">${hibernate.connection.datasource}</prop>
<prop key="hibernate.hbm2ddl.auto">${hibernate.hbm2ddl.auto}</prop>
<prop key="hibernate.show.sql">${hibernate.show.sql}</prop>
<prop key="hibernate.dialect">${hibernate.dialect}</prop>
</props>
</property>
<property name="packagesToScan">
<list>
<value>com.package.enities</value>
</list>
</property>
</bean>
При этом от pesistence.xml можно полностью отказаться.
