//////////////////////////////////////////////////////////////////////////////
// interface "RecommenderService" implementation
@Override
public List<ItemVO<Integer, Integer>> getActionHistory(
Integer tenantId,
Integer userId,
String sessionId,
Integer consideredActionTypeId,
Integer consideredItemTypeId,
Double ratingThreshold,
Integer numberOfLastActionsConsidered) {
List<ItemVO<Integer, Integer>> itemsActedOn =
actionService.getItemsByUserActionAndType(
tenantId,
userId,
sessionId,
consideredActionTypeId,
consideredItemTypeId,
ratingThreshold,
numberOfLastActionsConsidered);
return itemsActedOn;
}
private List<RecommendedItemVO<Integer, Integer>> doFiltering(
Integer tenantId,
Integer userId,
String sessionId,
Integer actionTypeId,
Integer itemTypeId,
List<RecommendedItemVO<Integer, Integer>> recommendedItems,
boolean useAveragePredictionValues) {
// filter duplicates
recommendedItems = filterDuplicates(recommendedItems, useAveragePredictionValues);
// filter out shortly acted on items
List<ItemVO<Integer, Integer>> itemsActedOn = null;
if (userId != null || sessionId != null) {
itemsActedOn =
actionService.getItemsByUserActionAndType(
tenantId, userId, sessionId, actionTypeId, itemTypeId, null, null);
}
if (itemsActedOn != null && itemsActedOn.size() > 0) {
filterAlreadyActedOn(recommendedItems, itemsActedOn);
}
return recommendedItems;
}
@Override
public RecommendationVO<Integer, Integer> getItemsBasedOnActionHistory(
Integer tenantId,
Integer userId,
String sessionId,
Integer consideredActionTypeId,
Integer consideredItemTypeId,
Double ratingThreshold,
Integer numberOfLastActionsConsidered,
Integer assocTypeId,
Integer requestedItemTypeId) {
List<ItemVO<Integer, Integer>> itemsActedOn =
actionService.getItemsByUserActionAndType(
tenantId,
userId,
sessionId,
consideredActionTypeId,
consideredItemTypeId,
ratingThreshold,
numberOfLastActionsConsidered);
List<AssociatedItemVO<Integer, Integer>> currentAssociatedItems;
List<RecommendedItemVO<Integer, Integer>> allRecommendedItems = null;
for (ItemVO<Integer, Integer> currentItem : itemsActedOn) {
currentAssociatedItems =
itemAssocService.getItemsTo(
currentItem,
assocTypeId,
requestedItemTypeId,
new IAConstraintVO<Integer, Integer>(
maximumNumberOfRelatedItemsPerItem, null, tenantId, true));
if (currentAssociatedItems != null) {
if (allRecommendedItems == null) {
allRecommendedItems = convertAssociatedItems(currentAssociatedItems, currentItem);
} else {
allRecommendedItems.addAll(convertAssociatedItems(currentAssociatedItems, currentItem));
}
}
}
// filter duplicates and history
if (filterResults) {
allRecommendedItems =
doFiltering(
tenantId,
userId,
sessionId,
consideredActionTypeId,
requestedItemTypeId,
allRecommendedItems,
DEFAULT_USE_AVERAGE_PREDICTION_VALUES_FOR_DUPLICATES);
}
// create recommendation object
RecommendationVO<Integer, Integer> recommendation =
new RecommendationVO<Integer, Integer>(
tenantId,
userId,
null,
requestedItemTypeId,
assocTypeId,
consideredActionTypeId,
RECOMMENDATION_STRATEGY_ITEMS_BASED_ON_ACTION_HISTORY,
EXPLANATION_ITEMS_BASED_ON_ACTION_HISTORY,
allRecommendedItems);
// HINT: implement an aspect (instead of directly using this) (Mantis Issue: #650)
if (recommendationHistoryService != null)
recommendationHistoryService.insertRecommendation(recommendation);
return recommendation;
}