com.planetj.taste.impl.recommender
Class AbstractRecommender

java.lang.Object
  com.planetj.taste.impl.recommender.AbstractRecommender

All Implemented Interfaces:

Refreshable, Recommender

Direct Known Subclasses:

GenericItemBasedRecommender, GenericUserBasedRecommender, ItemAverageRecommender, ItemUserAverageRecommender, SlopeOneRecommender, TreeClusteringRecommender, TreeClusteringRecommender2

public abstract class AbstractRecommender
extends java.lang.Object
implements Recommender

Author:

Sean Owen

Constructor Summary

protected

AbstractRecommender(DataModel dataModel)

Method Summary

protected java.util.Set<Item>	getAllOtherItems(User theUser)
DataModel	getDataModel()
java.util.List<RecommendedItem>	recommend(java.lang.Object userID, int howMany) Default implementation which just calls Recommender.recommend(Object, int,com.planetj.taste.recommender.Rescorer), with a Rescorer that does nothing.
void	refresh() Triggers "refresh" -- whatever that means -- of the implementation.
void	removePreference(java.lang.Object userID, java.lang.Object itemID) Default implementation which just calls DataModel.removePreference(Object, Object) (Object, Object)}.
void	setPreference(java.lang.Object userID, java.lang.Object itemID, double value) Default implementation which just calls DataModel.setPreference(Object, Object, double).

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.planetj.taste.recommender.Recommender

estimatePreference, recommend

Constructor Detail

AbstractRecommender

protected AbstractRecommender(DataModel dataModel)

Method Detail

recommend

@NotNull
public java.util.List<RecommendedItem> recommend(java.lang.Object userID,
                                                         int howMany)
                                          throws TasteException

Default implementation which just calls Recommender.recommend(Object, int,com.planetj.taste.recommender.Rescorer), with a Rescorer that does nothing.

Specified by:

recommend in interface Recommender

Parameters:

userID - user for which recommendations are to be computed

howMany - desired number of recommendations

Returns:

List of recommended RecommendedItems, ordered from most strongly recommend to least

Throws:

TasteException - if an error occurs while accessing the DataModel

setPreference

public void setPreference(java.lang.Object userID,
                          java.lang.Object itemID,
                          double value)
                   throws TasteException

Default implementation which just calls DataModel.setPreference(Object, Object, double).

Specified by:

setPreference in interface Recommender

Parameters:

userID - user to set preference for

itemID - item to set preference for

value - preference value

Throws:

java.lang.IllegalArgumentException - if userID or itemID is null, or if value is Double.NaN

TasteException - if an error occurs while accessing the DataModel

removePreference

public void removePreference(java.lang.Object userID,
                             java.lang.Object itemID)
                      throws TasteException

Default implementation which just calls DataModel.removePreference(Object, Object) (Object, Object)}.

Specified by:

removePreference in interface Recommender

Parameters:

userID - user from which to remove preference

itemID - item for which to remove preference

Throws:

java.lang.IllegalArgumentException - if userID or itemID is null

TasteException - if an error occurs while accessing the DataModel

getDataModel

@NotNull
public DataModel getDataModel()

Specified by:

getDataModel in interface Recommender

Returns:

DataModel used by this Recommender

refresh

public void refresh()

Triggers "refresh" -- whatever that means -- of the implementation. The general contract is that any Refreshable should always leave itself in a consistent, operational state, and that the refresh atomically updates internal state from old to new.

Specified by:

refresh in interface Refreshable

getAllOtherItems

@NotNull
protected java.util.Set<Item> getAllOtherItems(User theUser)
                                        throws TasteException

Parameters:

theUser - User being evaluated

Returns:

all Items in the DataModel for which the User has not expressed a preference

Throws:

TasteException - if an error occurs while listing Items