Java tutorial
/* * Copyright 2002-2018 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 * * https://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.orm.jpa; import javax.persistence.EntityManager; import org.springframework.lang.Nullable; import org.springframework.transaction.SavepointManager; import org.springframework.transaction.support.ResourceHolderSupport; import org.springframework.util.Assert; /** * Resource holder wrapping a JPA {@link EntityManager}. * {@link JpaTransactionManager} binds instances of this class to the thread, * for a given {@link javax.persistence.EntityManagerFactory}. * * <p>Also serves as a base class for {@link org.springframework.orm.hibernate5.SessionHolder}, * as of 5.1. * * <p>Note: This is an SPI class, not intended to be used by applications. * * @author Juergen Hoeller * @since 2.0 * @see JpaTransactionManager * @see EntityManagerFactoryUtils */ public class EntityManagerHolder extends ResourceHolderSupport { @Nullable private final EntityManager entityManager; private boolean transactionActive; @Nullable private SavepointManager savepointManager; public EntityManagerHolder(@Nullable EntityManager entityManager) { this.entityManager = entityManager; } public EntityManager getEntityManager() { Assert.state(this.entityManager != null, "No EntityManager available"); return this.entityManager; } protected void setTransactionActive(boolean transactionActive) { this.transactionActive = transactionActive; } protected boolean isTransactionActive() { return this.transactionActive; } protected void setSavepointManager(@Nullable SavepointManager savepointManager) { this.savepointManager = savepointManager; } @Nullable protected SavepointManager getSavepointManager() { return this.savepointManager; } @Override public void clear() { super.clear(); this.transactionActive = false; this.savepointManager = null; } }