org.apache.openjpa.slice.QueryTargetPolicy Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
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* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
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* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
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*/
package org.apache.openjpa.slice;
import java.util.List;
import java.util.Map;
/**
* Policy to select one or more of the physical databases referred as
* slice in which a given query will be executed.
*
* @author Pinaki Poddar
*
* @see DistributionPolicy
*
*/
public interface QueryTargetPolicy {
/**
* Gets the name of the slices where a given query will be executed.
*
* @param query The query string to be executed.
* @param params the bound parameters of the query
* @param language the query language
* @param slices list of names of the active slices. The ordering of
* the list is either explicit openjpa.slice.Names
property
* or implicit i.e. alphabetic order of available identifiers if
* openjpa.slice.Names
is unspecified.
* @param context generic persistence context managing the given instance.
*
* @return identifier of the slices. This names must match one of the
* given slice names.
*
* @see DistributedConfiguration#getActiveSliceNames()
*/
String[] getTargets(String query, Map