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.jpa;
016
017import java.util.List;
018
019import javax.persistence.EntityManager;
020import javax.persistence.EntityManagerFactory;
021import javax.persistence.spi.PersistenceUnitInfo;
022
023/**
024 * Responsible for creating an EntityManager as needed.
025 *
026 * @since 5.3
027 */
028public interface EntityManagerSource
029{
030    /**
031     * Creates an <code>EntityManager</code> for the given persistence unit name.
032     *
033     * @param persistenceUnitName the name of a persistence unit as defined in <code>persistence.xml<code>
034     * @return  EntityManager for the given persistence unit name
035     */
036    EntityManager create(String persistenceUnitName);
037
038    /**
039     * Gets the <code>EntityManagerFactory</code> for the given persistence unit name, creating it as necessary.
040     *
041     * @param persistenceUnitName the name of a persistence unit as defined in <code>persistence.xml<code>
042     *
043     * @return EntityManagerFactory for the given persistence unit name
044     */
045    EntityManagerFactory getEntityManagerFactory(String persistenceUnitName);
046
047    /**
048     * Get the list of {@linkplain PersistenceUnitInfo} parsed from <code>persistence.xml<code>.
049     *
050     * @return list of PersistenceUnitInfos
051     */
052    List<PersistenceUnitInfo> getPersistenceUnitInfos();
053}