    001// Copyright 2011 The Apache Software Foundation
    002//
    003// Licensed under the Apache License, Version 2.0 (the "License");
    004// you may not use this file except in compliance with the License.
    005// You may obtain a copy of the License at
    006//
    007// http://www.apache.org/licenses/LICENSE-2.0
    008//
    009// Unless required by applicable law or agreed to in writing, software
    010// distributed under the License is distributed on an "AS IS" BASIS,
    011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    012// See the License for the specific language governing permissions and
    013// limitations under the License.
    014
    015package org.apache.tapestry5.internal.jpa;
    016
    017import org.apache.tapestry5.ioc.internal.util.InternalUtils;
    018import org.apache.tapestry5.jpa.EntityManagerManager;
    019import org.apache.tapestry5.jpa.JpaConstants;
    020
    021import javax.persistence.EntityManager;
    022import javax.persistence.EntityManagerFactory;
    023import javax.persistence.PersistenceContext;
    024import javax.persistence.metamodel.EntityType;
    025import javax.persistence.metamodel.Metamodel;
    026import java.util.Map;
    027import java.util.Set;
    028
    029public class JpaInternalUtils
    030{
    031    public static PersistedEntity convertApplicationValueToPersisted(
    032            final EntityManagerManager entityManagerManager, final Object newValue)
    033    {
    034        final EntityManager em = getEntityManagerFactory(entityManagerManager, newValue);
    035
    036        final EntityManagerFactory emf = em.getEntityManagerFactory();
    037
    038        final Map<String, Object> properties = emf.getProperties();
    039
    040        final String persistenceUnitName = (String) properties
    041                .get(JpaConstants.PERSISTENCE_UNIT_NAME);
    042
    043        final Object id = emf.getPersistenceUnitUtil().getIdentifier(newValue);
    044
    045        return new PersistedEntity(newValue.getClass(), id, persistenceUnitName);
    046    }
    047
    048    private static EntityManager getEntityManagerFactory(
    049            final EntityManagerManager entityManagerManager, final Object entity)
    050    {
    051        final Map<String, EntityManager> entityManagers = entityManagerManager.getEntityManagers();
    052
    053        for (final EntityManager em : entityManagers.values())
    054        {
    055            final EntityManagerFactory emf = em.getEntityManagerFactory();
    056
    057            final Metamodel metamodel = emf.getMetamodel();
    058
    059            final Set<EntityType<?>> entities = metamodel.getEntities();
    060
    061            for (final EntityType<?> entityType : entities)
    062            {
    063                if (entityType.getJavaType() == entity.getClass())
    064                {
    065                    if (em.contains(entity))
    066                    {
    067                        return em;
    068                    }
    069                }
    070            }
    071        }
    072
    073        throw new IllegalArgumentException(
    074                String.format(
    075                        "Failed persisting the entity. The entity '%s' does not belong to any of the existing persistence contexts.",
    076                        entity));
    077    }
    078
    079    public static EntityManager getEntityManager(EntityManagerManager entityManagerManager,
    080                                                 PersistenceContext annotation)
    081    {
    082        String unitName = annotation == null ? null : annotation.unitName();
    083
    084        if (InternalUtils.isNonBlank(unitName))
    085            return entityManagerManager.getEntityManager(unitName);
    086
    087        Map<String, EntityManager> entityManagers = entityManagerManager.getEntityManagers();
    088
    089        if (entityManagers.size() == 1)
    090            return entityManagers.values().iterator().next();
    091
    092        throw new RuntimeException("Unable to locate a single EntityManager. " +
    093                "You must provide the persistence unit name as defined in the persistence.xml using the @PersistenceContext annotation.");
    094    }
    095}