在 Spring 的帮助下,我以符合 JPA 的方式做到了这一点。
<persistence-unit>
我的“persistence.xml”看起来是空的,元素中没有列出任何实体。
然后我编写了一个实现 PersistenceUnitPostProcessor 的类,如下所示:
import java.util.Set;
import javax.persistence.Entity;
import javax.persistence.MappedSuperclass;
import org.reflections.Reflections;
import org.reflections.scanners.TypeAnnotationsScanner;
import org.springframework.orm.jpa.persistenceunit.MutablePersistenceUnitInfo;
import org.springframework.orm.jpa.persistenceunit.PersistenceUnitPostProcessor;
public class ReflectionsPersistenceUnitPostProcessor implements PersistenceUnitPostProcessor {
private String reflectionsRoot;
private Logger log = LoggerFactory.getLogger(ReflectionsPersistenceUnitPostProcessor.class);
@Override
public void postProcessPersistenceUnitInfo(MutablePersistenceUnitInfo pui) {
Reflections r = new Reflections(this.reflectionsRoot, new TypeAnnotationsScanner());
Set<String> entityClasses = r.getStore().getTypesAnnotatedWith(Entity.class.getName());
Set<String> mappedSuperClasses = r.getStore().getTypesAnnotatedWith(MappedSuperclass.class.getName());
for (String clzz : mappedSuperClasses)
{
pui.addManagedClassName(clzz);
}
for (String clzz : entityClasses)
{
pui.addManagedClassName(clzz);
}
}
public String getReflectionsRoot() {
return reflectionsRoot;
}
public void setReflectionsRoot(String reflectionsRoot) {
this.reflectionsRoot = reflectionsRoot;
}
}
然后我像这样调整了我的spring上下文xml:
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="jpaVendorAdapter">
<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
<property name="showSql" value="false" />
<property name="generateDdl" value="true" />
<property name="databasePlatform" value="org.hibernate.dialect.MySQL5InnoDBDialect" />
</bean>
</property>
<property name="persistenceUnitName" value="GenericPersistenceUnit"/>
<property name="persistenceXmlLocation" value="classpath:META-INF/persistence.xml"/>
<property name="persistenceUnitPostProcessors">
<list>
<bean class="com.austinmichael.core.repository.ReflectionsPersistenceUnitPostProcessor">
<property name="reflectionsRoot" value="com.austinmichael"/>
</bean>
</list>
</property>
</bean>
注意ReflectionsPersistenceUnitPostProcessor
persistenceUnitPostProcessors 设置中的注册。
就是这样。在类路径上具有 JPA 实体或MappedSuperclass
注释的每个类都将添加到类路径中。我必须给反射一个包名称的前缀来扫描,这就是为什么com.austinmichael
存在。ReflectionsPersistenceUnitPostProcessor
如果您的实体不共享通用的包名称前缀,您可以根据需要使用不同的包名称前缀注册第二个。
但是,这现在与 JPAVendor 无关。