Hibernate example source code file (RevisionsOfEntityQuery.java)

This example Hibernate source code file (RevisionsOfEntityQuery.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Hibernate tags/keywords

auditentitiesconfiguration, auditreaderimplementor, class, hibernateproxy, list, map, map, number, number, object, object, revisionsofentityquery, string, string, util

The Hibernate RevisionsOfEntityQuery.java source code

/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as
 * indicated by the @author tags or express copyright attribution
 * statements applied by the authors.  All third-party contributions are
 * distributed under license by Red Hat Middleware LLC.
 *
 * This copyrighted material is made available to anyone wishing to use, modify,
 * copy, or redistribute it subject to the terms and conditions of the GNU
 * Lesser General Public License, as published by the Free Software Foundation.
 *
 * This program 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 Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this distribution; if not, write to:
 * Free Software Foundation, Inc.
 * 51 Franklin Street, Fifth Floor
 * Boston, MA  02110-1301  USA
 */
package org.hibernate.envers.query.impl;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import org.hibernate.envers.RevisionType;
import org.hibernate.envers.configuration.AuditConfiguration;
import org.hibernate.envers.configuration.AuditEntitiesConfiguration;
import org.hibernate.envers.exception.AuditException;
import org.hibernate.envers.query.criteria.AuditCriterion;
import org.hibernate.envers.reader.AuditReaderImplementor;
import org.hibernate.proxy.HibernateProxy;

/**
 * @author Adam Warski (adam at warski dot org)
 * @author Hern�n Chanfreau
 */
public class RevisionsOfEntityQuery extends AbstractAuditQuery {
    private final boolean selectEntitiesOnly;
    private final boolean selectDeletedEntities;

    public RevisionsOfEntityQuery(AuditConfiguration verCfg,
                                  AuditReaderImplementor versionsReader,
                                  Class<?> cls, boolean selectEntitiesOnly,
                                  boolean selectDeletedEntities) {
        super(verCfg, versionsReader, cls);

        this.selectEntitiesOnly = selectEntitiesOnly;
        this.selectDeletedEntities = selectDeletedEntities;
    }

	public RevisionsOfEntityQuery(AuditConfiguration verCfg,
			AuditReaderImplementor versionsReader, Class<?> cls, String entityName,
			boolean selectEntitiesOnly, boolean selectDeletedEntities) {
		super(verCfg, versionsReader, cls, entityName);

		this.selectEntitiesOnly = selectEntitiesOnly;
		this.selectDeletedEntities = selectDeletedEntities;
	}
	
    private Number getRevisionNumber(Map versionsEntity) {
        AuditEntitiesConfiguration verEntCfg = verCfg.getAuditEntCfg();

        String originalId = verEntCfg.getOriginalIdPropName();
        String revisionPropertyName = verEntCfg.getRevisionFieldName();

        Object revisionInfoObject = ((Map) versionsEntity.get(originalId)).get(revisionPropertyName);

        if (revisionInfoObject instanceof HibernateProxy) {
            return (Number) ((HibernateProxy) revisionInfoObject).getHibernateLazyInitializer().getIdentifier();
        } else {
            // Not a proxy - must be read from cache or with a join
            return verCfg.getRevisionInfoNumberReader().getRevisionNumber(revisionInfoObject);   
        }
    }

    @SuppressWarnings({"unchecked"})
    public List list() throws AuditException {
        AuditEntitiesConfiguration verEntCfg = verCfg.getAuditEntCfg();

        /*
        The query that should be executed in the versions table:
        SELECT e (unless another projection is specified) FROM ent_ver e, rev_entity r WHERE
          e.revision_type != DEL (if selectDeletedEntities == false) AND
          e.revision = r.revision AND
          (all specified conditions, transformed, on the "e" entity)
          ORDER BY e.revision ASC (unless another order or projection is specified)
         */      
        if (!selectDeletedEntities) {
            // e.revision_type != DEL AND
            qb.getRootParameters().addWhereWithParam(verEntCfg.getRevisionTypePropName(), "<>", RevisionType.DEL);
        }

        // all specified conditions, transformed
        for (AuditCriterion criterion : criterions) {
            criterion.addToQuery(verCfg, entityName, qb, qb.getRootParameters());
        }

        if (!hasProjection && !hasOrder) {
            String revisionPropertyPath = verEntCfg.getRevisionNumberPath();
            qb.addOrder(revisionPropertyPath, true);
        }

        if (!selectEntitiesOnly) {
            qb.addFrom(verCfg.getAuditEntCfg().getRevisionInfoEntityName(), "r");
            qb.getRootParameters().addWhere(verCfg.getAuditEntCfg().getRevisionNumberPath(), true, "=", "r.id", false);
        }

        List<Object> queryResult = buildAndExecuteQuery();
        if (hasProjection) {
            return queryResult;
        } else {
            List entities = new ArrayList();
            String revisionTypePropertyName = verEntCfg.getRevisionTypePropName();

            for (Object resultRow : queryResult) {
                Map versionsEntity;
                Object revisionData;

                if (selectEntitiesOnly) {
                    versionsEntity = (Map) resultRow;
                    revisionData = null;
                } else {
                    Object[] arrayResultRow = (Object[]) resultRow;
                    versionsEntity = (Map) arrayResultRow[0];
                    revisionData = arrayResultRow[1];
                }

                Number revision = getRevisionNumber(versionsEntity);
                
                Object entity = entityInstantiator.createInstanceFromVersionsEntity(entityName, versionsEntity, revision);

                if (!selectEntitiesOnly) {
                    entities.add(new Object[] { entity, revisionData, versionsEntity.get(revisionTypePropertyName) });
                } else {
                    entities.add(entity);
                }
            }

            return entities;
        }
    }
}