/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* License: GNU Lesser General Public License (LGPL), version 2.1 or later.
* See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
*/
package org.hibernate.envers.internal.entities.mapper.relation.query;
import org.hibernate.envers.configuration.internal.AuditEntitiesConfiguration;
import org.hibernate.envers.internal.entities.mapper.relation.MiddleComponentData;
import org.hibernate.envers.internal.entities.mapper.relation.MiddleIdData;
import org.hibernate.envers.internal.tools.query.Parameters;
import org.hibernate.envers.internal.tools.query.QueryBuilder;
import org.hibernate.envers.strategy.AuditStrategy;
import static org.hibernate.envers.internal.entities.mapper.relation.query.QueryConstants.DEL_REVISION_TYPE_PARAMETER;
import static org.hibernate.envers.internal.entities.mapper.relation.query.QueryConstants.MIDDLE_ENTITY_ALIAS;
import static org.hibernate.envers.internal.entities.mapper.relation.query.QueryConstants.REVISION_PARAMETER;
/**
* Selects data from a relation middle-table only.
*
* @author Adam Warski (adam at warski dot org)
* @author Lukasz Antoniak (lukasz dot antoniak at gmail dot com)
*/
public final class OneEntityQueryGenerator extends AbstractRelationQueryGenerator {
private final String queryString;
private final String queryRemovedString;
public OneEntityQueryGenerator(
AuditEntitiesConfiguration verEntCfg, AuditStrategy auditStrategy,
String versionsMiddleEntityName, MiddleIdData referencingIdData,
boolean revisionTypeInId, MiddleComponentData... componentData) {
super( verEntCfg, referencingIdData, revisionTypeInId );
/*
* The valid query that we need to create:
* SELECT ee FROM middleEntity ee WHERE
* (only entities referenced by the association; id_ref_ing = id of the referencing entity)
* ee.originalId.id_ref_ing = :id_ref_ing AND
*
* (the association at revision :revision)
* --> for DefaultAuditStrategy:
* ee.revision = (SELECT max(ee2.revision) FROM middleEntity ee2
* WHERE ee2.revision <= :revision AND ee2.originalId.* = ee.originalId.*)
*
* --> for ValidityAuditStrategy:
* ee.revision <= :revision and (ee.endRevision > :revision or ee.endRevision is null)
*
* AND
*
* (only non-deleted entities and associations)
* ee.revision_type != DEL
*/
final QueryBuilder commonPart = commonQueryPart( versionsMiddleEntityName );
final QueryBuilder validQuery = commonPart.deepCopy();
final QueryBuilder removedQuery = commonPart.deepCopy();
createValidDataRestrictions(
auditStrategy, versionsMiddleEntityName, validQuery, validQuery.getRootParameters(), true, componentData
);
createValidAndRemovedDataRestrictions( auditStrategy, versionsMiddleEntityName, removedQuery, componentData );
queryString = queryToString( validQuery );
queryRemovedString = queryToString( removedQuery );
}
/**
* Compute common part for both queries.
*/
private QueryBuilder commonQueryPart(String versionsMiddleEntityName) {
// SELECT ee FROM middleEntity ee
final QueryBuilder qb = new QueryBuilder( versionsMiddleEntityName, MIDDLE_ENTITY_ALIAS );
qb.addProjection( null, MIDDLE_ENTITY_ALIAS, null, false );
// WHERE
// ee.originalId.id_ref_ing = :id_ref_ing
referencingIdData.getPrefixedMapper().addNamedIdEqualsToQuery(
qb.getRootParameters(),
verEntCfg.getOriginalIdPropName(),
true
);
return qb;
}
/**
* Creates query restrictions used to retrieve only actual data.
*/
private void createValidDataRestrictions(
AuditStrategy auditStrategy, String versionsMiddleEntityName,
QueryBuilder qb, Parameters rootParameters, boolean inclusive,
MiddleComponentData... componentData) {
final String revisionPropertyPath = verEntCfg.getRevisionNumberPath();
final String originalIdPropertyName = verEntCfg.getOriginalIdPropName();
final String eeOriginalIdPropertyPath = MIDDLE_ENTITY_ALIAS + "." + originalIdPropertyName;
// (with ee association at revision :revision)
// --> based on auditStrategy (see above)
auditStrategy.addAssociationAtRevisionRestriction(
qb, rootParameters, revisionPropertyPath, verEntCfg.getRevisionEndFieldName(), true,
referencingIdData, versionsMiddleEntityName, eeOriginalIdPropertyPath, revisionPropertyPath,
originalIdPropertyName, MIDDLE_ENTITY_ALIAS, inclusive, componentData
);
// ee.revision_type != DEL
rootParameters.addWhereWithNamedParam( getRevisionTypePath(), "!=", DEL_REVISION_TYPE_PARAMETER );
}
/**
* Create query restrictions used to retrieve actual data and deletions that took place at exactly given revision.
*/
private void createValidAndRemovedDataRestrictions(
AuditStrategy auditStrategy, String versionsMiddleEntityName,
QueryBuilder remQb, MiddleComponentData... componentData) {
final Parameters disjoint = remQb.getRootParameters().addSubParameters( "or" );
// Restrictions to match all valid rows.
final Parameters valid = disjoint.addSubParameters( "and" );
// Restrictions to match all rows deleted at exactly given revision.
final Parameters removed = disjoint.addSubParameters( "and" );
// Excluding current revision, because we need to match data valid at the previous one.
createValidDataRestrictions( auditStrategy, versionsMiddleEntityName, remQb, valid, false, componentData );
// ee.revision = :revision
removed.addWhereWithNamedParam( verEntCfg.getRevisionNumberPath(), "=", REVISION_PARAMETER );
// ee.revision_type = DEL
removed.addWhereWithNamedParam( getRevisionTypePath(), "=", DEL_REVISION_TYPE_PARAMETER );
}
@Override
protected String getQueryString() {
return queryString;
}
@Override
protected String getQueryRemovedString() {
return queryRemovedString;
}
}