org.springframework.batch.item.database.Hibernate5ItemWriter.java Source code

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Here is the source code for org.springframework.batch.item.database.Hibernate5ItemWriter.java

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/*
 * Copyright 2006-2013 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.batch.item.database;

import java.util.List;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.context.spi.CurrentSessionContext;
import org.springframework.batch.item.ItemWriter;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.orm.hibernate5.HibernateOperations;
import org.springframework.util.Assert;

/**
 * {@link ItemWriter} that uses a Hibernate session to save or update entities
 * that are not part of the current Hibernate session. It will also flush the
 * session after writing (i.e. at chunk boundaries if used in a Spring Batch
 * TaskletStep). It will also clear the session on write
 * default (see {@link #setClearSession(boolean) clearSession} property).<br>
 * <br>
 *
 * The writer is thread-safe once properties are set (normal singleton behavior)
 * if a {@link CurrentSessionContext} that uses only one session per thread is
 * used.
 *
 * @author Dave Syer
 * @author Thomas Risberg
 * @author Michael Minella
 *
 */
public class Hibernate5ItemWriter<T> implements ItemWriter<T>, InitializingBean {

    protected static final Log logger = LogFactory.getLog(Hibernate5ItemWriter.class);

    private HibernateOperations hibernateTemplate;
    private SessionFactory sessionFactory;

    private boolean clearSession = true;

    /**
     * Flag to indicate that the session should be cleared and flushed at the
     * end of the write (default true).
     *
     * @param clearSession
     *            the flag value to set
     */
    public void setClearSession(boolean clearSession) {
        this.clearSession = clearSession;
    }

    /**
     * Public setter for the {@link HibernateOperations} property.
     *
     * @param hibernateTemplate
     *            the hibernateTemplate to set
     * @deprecated As of 2.2 in favor of using Hibernate's session management APIs directly
     */
    public void setHibernateTemplate(HibernateOperations hibernateTemplate) {
        this.hibernateTemplate = hibernateTemplate;
    }

    /**
     * Set the Hibernate SessionFactory to be used internally.
     *
     * @param sessionFactory session factory to be used by the writer
     */
    public void setSessionFactory(SessionFactory sessionFactory) {
        this.sessionFactory = sessionFactory;
    }

    /**
     * Check mandatory properties - there must be a hibernateTemplate.
     */
    @Override
    public void afterPropertiesSet() {
        Assert.state(!(hibernateTemplate == null && sessionFactory == null),
                "Either HibernateOperations or SessionFactory must be provided");
    }

    /**
     * Save or update any entities not in the current hibernate session and then
     * flush the hibernate session.
     *
     * @see org.springframework.batch.item.ItemWriter#write(java.util.List)
     */
    @Override
    public void write(List<? extends T> items) {
        if (sessionFactory == null) {
            doWrite(hibernateTemplate, items);
            hibernateTemplate.flush();
            if (clearSession) {
                hibernateTemplate.clear();
            }
        } else {
            doWrite(sessionFactory, items);
            sessionFactory.getCurrentSession().flush();
            if (clearSession) {
                sessionFactory.getCurrentSession().clear();
            }
        }
    }

    /**
     * Do perform the actual write operation using Hibernate's API.
     * This can be overridden in a subclass if necessary.
     *
     * @param sessionFactory Hibernate SessionFactory to be used
     * @param items the list of items to use for the write
     */
    protected void doWrite(SessionFactory sessionFactory, List<? extends T> items) {
        if (logger.isDebugEnabled()) {
            logger.debug("Writing to Hibernate with " + items.size() + " items.");
        }

        Session currentSession = sessionFactory.getCurrentSession();

        if (!items.isEmpty()) {
            long saveOrUpdateCount = 0;
            for (T item : items) {
                if (!currentSession.contains(item)) {
                    currentSession.saveOrUpdate(item);
                    saveOrUpdateCount++;
                }
            }
            if (logger.isDebugEnabled()) {
                logger.debug(saveOrUpdateCount + " entities saved/updated.");
                logger.debug((items.size() - saveOrUpdateCount) + " entities found in session.");
            }
        }
    }

    /**
     * Do perform the actual write operation using {@link HibernateOperations}.
     * This can be overridden in a subclass if necessary.
     *
     * @param hibernateTemplate
     *            the HibernateTemplate to use for the operation
     * @param items
     *            the list of items to use for the write
     * @deprecated As of 2.2 in favor of using Hibernate's session management APIs directly
     */
    protected void doWrite(HibernateOperations hibernateTemplate, List<? extends T> items) {

        if (logger.isDebugEnabled()) {
            logger.debug("Writing to Hibernate with " + items.size() + " items.");
        }

        if (!items.isEmpty()) {
            long saveOrUpdateCount = 0;
            for (T item : items) {
                if (!hibernateTemplate.contains(item)) {
                    hibernateTemplate.saveOrUpdate(item);
                    saveOrUpdateCount++;
                }
            }
            if (logger.isDebugEnabled()) {
                logger.debug(saveOrUpdateCount + " entities saved/updated.");
                logger.debug((items.size() - saveOrUpdateCount) + " entities found in session.");
            }
        }

    }

}