    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.Map;
    018
    019import javax.persistence.EntityManager;
    020
    021/**
    022 * Manages <code>EntityManager</code>s for the current thread.
    023 * An <code>EntityManager</code> is created as needed and closed at the end of each request.
    024 *
    025 * <p/>
    026 *
    027 * The implementation of this service is per-thread.
    028 *
    029 * @since 5.3
    030 */
    031public interface EntityManagerManager
    032{
    033    /**
    034     * Gets the active <code>EntityManager</code> for this request, creating it as necessary.
    035     *
    036     * @param persistenceUnitName the name of a persistence unit as defined in <code>persistence.xml<code>
    037     * @return EntityManager for the persistence unit,
    038     */
    039    EntityManager getEntityManager(String persistenceUnitName);
    040
    041    /**
    042     * Gets all active <code>EntityManager</code>s for this request, creating them as necessary.
    043     *
    044     * @return Map in which persistence unit names are associated with EntityManagers
    045     */
    046    Map<String, EntityManager> getEntityManagers();
    047}