| /* |
| * Copyright (c) 2011, 2021 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: |
| // James Sutherland (Oracle) - initial API and implementation |
| package org.eclipse.persistence.descriptors.partitioning; |
| |
| import org.eclipse.persistence.descriptors.ClassDescriptor; |
| import org.eclipse.persistence.internal.helper.DatabaseField; |
| import org.eclipse.persistence.internal.sessions.AbstractSession; |
| import org.eclipse.persistence.sessions.server.ClientSession; |
| |
| /** |
| * PUBLIC: |
| * FieldPartitioningPolicy partitions access to a database cluster by a field value from the object, |
| * such as the object's id, location, or tenant. |
| * All write or read request for object's with that value are sent to the server. |
| * If a query does not include the field as a parameter, then it can either be sent |
| * to all server's and unioned, or left to the sesion's default behavior. |
| * @author James Sutherland |
| * @since EclipseLink 2.2 |
| */ |
| public abstract class FieldPartitioningPolicy extends PartitioningPolicy { |
| |
| /** The column to partition by. */ |
| protected DatabaseField partitionField; |
| |
| /** If query does not have the partition field in it, should the query be sent to all databases. */ |
| protected boolean unionUnpartitionableQueries = false; |
| |
| protected FieldPartitioningPolicy() { |
| super(); |
| } |
| |
| protected FieldPartitioningPolicy(String partitionField) { |
| super(); |
| this.partitionField = new DatabaseField(partitionField); |
| } |
| |
| protected FieldPartitioningPolicy(String partitionField, boolean unionUnpartitionableQueries) { |
| this(partitionField); |
| this.unionUnpartitionableQueries = unionUnpartitionableQueries; |
| } |
| |
| /** |
| * PUBLIC: |
| * Return the database column or query parameter to partition queries by. |
| * This is the table column name, not the class attribute name. |
| * The column value must be included in the query and should normally be part of the object's Id. |
| * This can also be the name of a query parameter. |
| * If a query does not contain the field the query will not be partitioned. |
| */ |
| public DatabaseField getPartitionField() { |
| return partitionField; |
| } |
| |
| /** |
| * PUBLIC: |
| * Set the database column or query parameter to partition queries by. |
| * This is the table column name, not the class attribute name. |
| * The column value must be included in the query and should normally be part of the object's Id. |
| * This can also be the name of a query parameter. |
| * If a query does not contain the field the query will not be partitioned. |
| */ |
| public void setPartitionField(DatabaseField partitionField) { |
| this.partitionField = partitionField; |
| } |
| |
| /** |
| * PUBLIC: |
| * Return the database column or query parameter to partition queries by. |
| * This is the table column name, not the class attribute name. |
| * The column value must be included in the query and should normally be part of the object's Id. |
| * This can also be the name of a query parameter. |
| * If a query does not contain the field the query will not be partitioned. |
| */ |
| public String getPartitionFieldName() { |
| return getPartitionField().getName(); |
| } |
| |
| /** |
| * PUBLIC: |
| * Set the database column or query parameter to partition queries by. |
| * This is the table column name, not the class attribute name. |
| * The column value must be included in the query and should normally be part of the object's Id. |
| * This can also be the name of a query parameter. |
| * If a query does not contain the field the query will not be partitioned. |
| */ |
| public void setPartitionField(String partitionField) { |
| this.partitionField = new DatabaseField(partitionField); |
| } |
| |
| /** |
| * PUBLIC: |
| * Return if queries that do not contain the partition field should be sent |
| * to every database and have the result unioned. |
| */ |
| public boolean getUnionUnpartitionableQueries() { |
| return unionUnpartitionableQueries; |
| } |
| |
| /** |
| * PUBLIC: |
| * Set if queries that do not contain the partition field should be sent |
| * to every database and have the result unioned. |
| */ |
| public void setUnionUnpartitionableQueries(boolean unionUnpartitionableQueries) { |
| this.unionUnpartitionableQueries = unionUnpartitionableQueries; |
| } |
| |
| /** |
| * INTERNAL: |
| * If persist should be partitioned, extra value from object. |
| */ |
| protected Object extractPartitionValueForPersist(AbstractSession session, Object object, ClassDescriptor descriptor) { |
| if (!session.isClientSession()) { |
| return null; |
| } |
| ClientSession client = (ClientSession)session; |
| // Only assign the connection if exclusive. |
| if (!client.isExclusiveIsolatedClientSession() || client.hasWriteConnection()) { |
| return null; |
| } |
| return descriptor.getObjectBuilder().extractValueFromObjectForField(object, this.partitionField, session); |
| } |
| } |