org.eclipse.persistence.descriptors.AllFieldsLockingPolicy Maven / Gradle / Ivy
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/*
* Copyright (c) 1998, 2020 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0 which is available at
* http://www.eclipse.org/legal/epl-2.0,
* or the Eclipse Distribution License v. 1.0 which is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
*/
// Contributors:
// Oracle - initial API and implementation from Oracle TopLink
package org.eclipse.persistence.descriptors;
import java.util.*;
import org.eclipse.persistence.internal.helper.*;
import org.eclipse.persistence.internal.sessions.AbstractRecord;
import org.eclipse.persistence.queries.*;
/**
* Purpose: An implementation of the OptimisticLockingPolicy interface.
* This policy compares every field in the table in the WHERE clause
* when doing an update or a delete. If any field has been changed, an
* optimistic locking exception will be thrown.
* NOTE: This policy can only be used inside a unit of work.
*
* @since TopLink 2.1
* @author Peter Krogh
*/
public class AllFieldsLockingPolicy extends FieldsLockingPolicy {
/**
* PUBLIC:
* Create a new all fields locking policy.
* A field locking policy is based on locking on all fields by comparing with their previous values to detect field-level collisions.
* Note: the unit of work must be used for all updates when using field locking.
*/
public AllFieldsLockingPolicy() {
super();
}
/**
* INTERNAL:
* Values to be included in the locking mechanism are added
* to the translation row. Set the translation row to all the original field values.
*/
@Override
public void addLockValuesToTranslationRow(ObjectLevelModifyQuery query) {
verifyUsage(query.getSession());
query.setTranslationRow(descriptor.getObjectBuilder().buildRowForWhereClause(query));
}
/**
* INTERNAL:
* Returns the fields that should be compared in the where clause.
* In this case, it is all the fields, except for the primary key
* and class indicator.
*/
@Override
protected List getFieldsToCompare(DatabaseTable table, AbstractRecord transRow, AbstractRecord modifyRow) {
return getAllNonPrimaryKeyFields(table);
}
}