| /* |
| * 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 org.eclipse.persistence.queries.ObjectLevelReadQuery; |
| import org.eclipse.persistence.exceptions.ValidationException; |
| |
| /** |
| * <p> <b>Description</b>: This policy is used to configure bean level pessimistic locking feature. |
| * It is set on the CMPPolicy instance of the ClassDescriptor |
| * |
| * Note that bean is not pessimistic locked in the following scenarios: |
| * <ul> |
| * <li> No presence of a JTA transaction |
| * <li> The current transaction is created and started by the Container for the invoking entity bean's method only. (i.e. invoke a business method without a client transaction) |
| * <li> The bean has already been pessimistic locked in the current transaction |
| * <li> Execution of ejbSelect |
| * <li> Traversing relationship does not lock the returned result. |
| * </ul> |
| * <p> |
| * <b>Responsibilities</b>: |
| * <ul> |
| * <li> Configure locking modes of WAIT or NO_WAIT |
| * <li> Provide utility to configure an ObjectLevelReadQuery with pessimistic locking based on this policy. |
| * </ul> |
| * |
| * @see org.eclipse.persistence.descriptors.CMPPolicy |
| * |
| * @since TopLink 10.1.3 |
| */ |
| public class PessimisticLockingPolicy implements Cloneable, java.io.Serializable { |
| protected short lockingMode; |
| |
| public PessimisticLockingPolicy() { |
| lockingMode = ObjectLevelReadQuery.LOCK; |
| } |
| |
| /** |
| * PUBLIC: |
| * Return locking mode. Default locking mode is ObjectLevelReadQuery.LOCK. |
| * @return short locking mode value of ObjectLevelReadQuery.LOCK or ObjectLevelReadQuery.LOCK_NOWAIT |
| */ |
| public short getLockingMode() { |
| return lockingMode; |
| } |
| |
| /** |
| * PUBLIC: |
| * Set locking mode. If the mode is not a valid value, the locking mode is unchanged. |
| * @param mode must be value of ObjectLevelReadQuery.LOCK or ObjectLevelReadQuery.LOCK_NOWAIT |
| */ |
| public void setLockingMode(short mode) { |
| if ((mode == ObjectLevelReadQuery.LOCK) || (mode == ObjectLevelReadQuery.LOCK_NOWAIT)) { |
| lockingMode = mode; |
| } else { |
| throw ValidationException.invalidMethodArguments(); |
| } |
| } |
| |
| /** |
| * INTERNAL: |
| * Clone the policy |
| */ |
| @Override |
| public Object clone() { |
| PessimisticLockingPolicy clone = new PessimisticLockingPolicy(); |
| clone.setLockingMode(this.lockingMode); |
| return clone; |
| } |
| } |