/*
* Copyright (c) 2010 Lockheed Martin Corporation
*
* Licensed 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 "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.eurekastreams.server.persistence.mappers;
import java.util.List;
/**
* Mapper to look up items by a key that's translated to the item's id.
*
* @param <PointerType>
* the type of data to use to look up the item's id
* @param <ValueType>
* the item type to return
*/
public class GetItemsByPointerIdsMapper<PointerType, ValueType> implements
DomainMapper<List<PointerType>, List<ValueType>>
{
/**
* Mapper to look up the ids by the pointer ids.
*/
private DomainMapper<List<PointerType>, List<Long>> pointersToIdMapper;
/**
* Mapper to look up the item by id.
*/
private DomainMapper<List<Long>, List<ValueType>> itemsByIdMapper;
/**
* Constructor.
*
* @param inPointersToIdMapper
* Mapper to look up the ids by the pointer ids.
* @param inItemsByIdMapper
* Mapper to look up the item by id.
*/
public GetItemsByPointerIdsMapper(final DomainMapper<List<PointerType>, List<Long>> inPointersToIdMapper,
final DomainMapper<List<Long>, List<ValueType>> inItemsByIdMapper)
{
pointersToIdMapper = inPointersToIdMapper;
itemsByIdMapper = inItemsByIdMapper;
}
/**
* Lookup the items by their look-up fields.
*
* @param inPointerIds
* the pointers to use to lookup the item
* @return the items referenced by the input pointers
*/
@Override
public List<ValueType> execute(final List<PointerType> inPointerIds)
{
List<Long> pointersToIds = pointersToIdMapper.execute(inPointerIds);
return itemsByIdMapper.execute(pointersToIds);
}
}