org.lenskit.basic

Class AbstractItemScorer

java.lang.Object

org.lenskit.basic.AbstractItemScorer

All Implemented Interfaces:

ItemScorer

Direct Known Subclasses:

BiasedMFItemScorer, BiasItemScorer, ConstantItemScorer, FallbackItemScorer, ItemItemScorer, ItemMeanRatingItemScorer, LeastSquaresItemScorer, PopularityRankItemScorer, PrecomputedItemScorer, SimpleCachingItemScorer, SlopeOneItemScorer, UserMeanItemScorer, UserUserItemScorer

public abstract class AbstractItemScorer
extends Object
implements ItemScorer

Base class to make item scorers easier to implement. Delegates all score methods to ItemScorer.scoreWithDetails(long, Collection).

Since:

3.0

Constructor Summary

Constructors

Constructor and Description
AbstractItemScorer()

Method Summary

Modifier and Type	Method and Description
Map<Long,Double>	score(long user, Collection<Long> items) Score a collection of items.
Result	score(long user, long item) Score a single item.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.lenskit.api.ItemScorer

scoreWithDetails

Constructor Detail

AbstractItemScorer

public AbstractItemScorer()

Method Detail

score

public Result score(long user,
                    long item)

Score a single item.

This implementation delegates to ItemScorer.scoreWithDetails(long, Collection).

Specified by:

score in interface ItemScorer

Parameters:

user - The user ID for whom to generate a score.

item - The item ID to score.

Returns:

The score, or null if no score can be generated.

score

@Nonnull
public Map<Long,Double> score(long user,
                                        @Nonnull
                                        Collection<Long> items)

Score a collection of items.

This implementation delegates to ItemScorer.scoreWithDetails(long, Collection).

Specified by:

score in interface ItemScorer

Parameters:

user - The user ID for whom to generate scores.

items - The item to score.

Returns:

The scores for the items. This result set may not contain all requested items.