org.transitime.db.structs.ActiveRevisions.java Source code

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Here is the source code for org.transitime.db.structs.ActiveRevisions.java

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/*
 * This file is part of Transitime.org
 * 
 * Transitime.org is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License (GPL) as published by
 * the Free Software Foundation, either version 3 of the License, or
 * any later version.
 *
 * Transitime.org is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Transitime.org .  If not, see <http://www.gnu.org/licenses/>.
 */

package org.transitime.db.structs;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

import org.hibernate.HibernateException;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.annotations.DynamicUpdate;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.transitime.db.hibernate.HibernateUtils;

/**
 * For keeping track of current revisions. This table should only have a single
 * row, one that specified the configRev and the travelTimesRev currently being
 * used.
 *
 * @author SkiBu Smith
 *
 */
@Entity
@DynamicUpdate
public class ActiveRevisions {

    // Need a generated ID since Hibernate required some type
    // of ID. Both configRev and travelTimesRev
    // might get updated and with Hibernate you can't read in an
    // object, modify an ID and then write it out again. Therefore
    // configRev and travelTimesRev can't be an ID. This means
    // that need a separate ID. Yes, somewhat peculiar.
    @Id
    @Column
    @GeneratedValue
    private Integer id;

    // For the configuration data for routes, stops, schedule, etc.
    @Column
    private int configRev;

    // For the travel time configuration data. Updated independently of
    // configRev.
    @Column
    private int travelTimesRev;

    private static final Logger logger = LoggerFactory.getLogger(ActiveRevisions.class);

    /********************** Member Functions **************************/

    /**
     * Constructor. Sets the revisions to default values of -1.
     */
    public ActiveRevisions() {
        configRev = -1;
        travelTimesRev = -1;
    }

    /**
     * Gets the ActiveRevisions object using the passed in database session.
     * 
     * @param session
     * @return the ActiveRevisions
     * @throws HibernateException
     */
    public static ActiveRevisions get(Session session) throws HibernateException {
        // There should only be a single object so don't need a WHERE clause
        String hql = "FROM ActiveRevisions";
        Query query = session.createQuery(hql);
        ActiveRevisions activeRevisions = null;
        try {
            activeRevisions = (ActiveRevisions) query.uniqueResult();
        } catch (Exception e) {
            System.err
                    .println("Exception when reading ActiveRevisions object " + "from database so will create it");
        } finally {
            // If couldn't read from db use default values and write the
            // object to the database.
            if (activeRevisions == null) {
                activeRevisions = new ActiveRevisions();
                session.persist(activeRevisions);
            }
        }

        // Return the object
        return activeRevisions;
    }

    /**
     * Reads revisions from database.
     * 
     * @param agencyId
     * @return
     * @throws HibernateException
     */
    public static ActiveRevisions get(String agencyId) throws HibernateException {
        Session session = null;
        try {
            // Get from db
            session = HibernateUtils.getSession(agencyId);
            ActiveRevisions activeRevisions = get(session);

            // Return the object
            return activeRevisions;
        } catch (HibernateException e) {
            logger.error("Exception in ActiveRevisions.get(). {}", e.getMessage(), e);
        } finally {
            // Always make sure session gets closed
            if (session != null)
                session.close();
        }

        return null;
    }

    /**
     * Updates configRev member and calls saveOrUpdate(this) on the session.
     * Useful for when want to update the value but don't want to commit it
     * until all other data is also written out successfully.
     * 
     * @param session
     * @param configRev
     */
    public void setConfigRev(Session session, int configRev) {
        this.configRev = configRev;
        session.saveOrUpdate(this);
    }

    /**
     * Updates travelTimeRev member and calls saveOrUpdate(this) on the session.
     * Useful for when want to update the value but don't want to commit it
     * until all other data is also written out successfully.
     * 
     * @param session
     * @param travelTimeRev
     */
    public void setTravelTimesRev(Session session, int travelTimeRev) {
        this.travelTimesRev = travelTimeRev;
        session.saveOrUpdate(this);
    }

    /**
     * Sets the travel time rev. Doesn't write it to db though. To write to db
     * should flush the session that the object was read in by.
     * 
     * @param travelTimeRev
     */
    public void setTravelTimesRev(int travelTimeRev) {
        this.travelTimesRev = travelTimeRev;
    }

    /**
     * Sets the config rev. Doesn't write it to db though. To write to db
     * should flush the session that the object was read in by.
     * 
     * @param configRev
     */
    public void setConfigRev(int configRev) {
        this.configRev = configRev;
    }

    public int getConfigRev() {
        return configRev;
    }

    public int getTravelTimesRev() {
        return travelTimesRev;
    }

    /**
     * @return True if both the configRev and travelTimesRev are both valid.
     */
    public boolean isValid() {
        return configRev >= 0 && travelTimesRev >= 0;
    }

    @Override
    public String toString() {
        return "ActiveRevisions [" + "configRev=" + configRev + ", travelTimesRev=" + travelTimesRev + "]";
    }

}