/*
* Copyright 2011 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.data.jpa.repository.cdi;
import java.lang.annotation.Annotation;
import java.lang.reflect.Type;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import javax.enterprise.event.Observes;
import javax.enterprise.inject.UnsatisfiedResolutionException;
import javax.enterprise.inject.spi.AfterBeanDiscovery;
import javax.enterprise.inject.spi.Bean;
import javax.enterprise.inject.spi.BeanManager;
import javax.enterprise.inject.spi.ProcessBean;
import javax.persistence.EntityManager;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.data.repository.cdi.CdiRepositoryBean;
import org.springframework.data.repository.cdi.CdiRepositoryExtensionSupport;
/**
* A portable CDI extension which registers beans for Spring Data JPA repositories.
*
* @author Dirk Mahler
* @author Oliver Gierke
* @author Mark Paluch
*/
public class JpaRepositoryExtension extends CdiRepositoryExtensionSupport {
private static final Logger LOGGER = LoggerFactory.getLogger(JpaRepositoryExtension.class);
private final Map<Set<Annotation>, Bean<EntityManager>> entityManagers = new HashMap<Set<Annotation>, Bean<EntityManager>>();
public JpaRepositoryExtension() {
LOGGER.info("Activating CDI extension for Spring Data JPA repositories.");
}
/**
* Implementation of a an observer which checks for EntityManager beans and stores them in {@link #entityManagers} for
* later association with corresponding repository beans.
*
* @param <X> The type.
* @param processBean The annotated type as defined by CDI.
*/
@SuppressWarnings("unchecked")
<X> void processBean(@Observes ProcessBean<X> processBean) {
Bean<X> bean = processBean.getBean();
for (Type type : bean.getTypes()) {
// Check if the bean is an EntityManager.
if (type instanceof Class<?> && EntityManager.class.isAssignableFrom((Class<?>) type)) {
Set<Annotation> qualifiers = new HashSet<Annotation>(bean.getQualifiers());
if (bean.isAlternative() || !entityManagers.containsKey(qualifiers)) {
LOGGER.debug("Discovered '{}' with qualifiers {}.", EntityManager.class.getName(), qualifiers);
entityManagers.put(qualifiers, (Bean<EntityManager>) bean);
}
}
}
}
/**
* Implementation of a an observer which registers beans to the CDI container for the detected Spring Data
* repositories.
* <p>
* The repository beans are associated to the EntityManagers using their qualifiers.
*
* @param beanManager The BeanManager instance.
*/
void afterBeanDiscovery(@Observes AfterBeanDiscovery afterBeanDiscovery, BeanManager beanManager) {
for (Entry<Class<?>, Set<Annotation>> entry : getRepositoryTypes()) {
Class<?> repositoryType = entry.getKey();
Set<Annotation> qualifiers = entry.getValue();
// Create the bean representing the repository.
CdiRepositoryBean<?> repositoryBean = createRepositoryBean(repositoryType, qualifiers, beanManager);
LOGGER.info("Registering bean for '{}' with qualifiers {}.", repositoryType.getName(), qualifiers);
// Register the bean to the extension and the container.
registerBean(repositoryBean);
afterBeanDiscovery.addBean(repositoryBean);
}
}
/**
* Creates a {@link Bean}.
*
* @param <T> The type of the repository.
* @param repositoryType The class representing the repository.
* @param beanManager The BeanManager instance.
* @return The bean.
*/
private <T> CdiRepositoryBean<T> createRepositoryBean(Class<T> repositoryType, Set<Annotation> qualifiers,
BeanManager beanManager) {
// Determine the entity manager bean which matches the qualifiers of the repository.
Bean<EntityManager> entityManagerBean = entityManagers.get(qualifiers);
if (entityManagerBean == null) {
throw new UnsatisfiedResolutionException(String.format("Unable to resolve a bean for '%s' with qualifiers %s.",
EntityManager.class.getName(), qualifiers));
}
// Construct and return the repository bean.
return new JpaRepositoryBean<T>(beanManager, entityManagerBean, qualifiers, repositoryType,
getCustomImplementationDetector());
}
}