org.lenskit.data.ratings

Class AbstractRatingVectorPDAO

java.lang.Object

org.lenskit.data.ratings.AbstractRatingVectorPDAO

All Implemented Interfaces:

RatingVectorPDAO

Direct Known Subclasses:

CountSumRatingVectorPDAO, EntityCountRatingVectorPDAO

public abstract class AbstractRatingVectorPDAO
extends java.lang.Object
implements RatingVectorPDAO

Base class for helping construct rating vector proxy DAOs.

Field Summary

Fields

Modifier and Type	Field and Description
protected DataAccessObject	dao

Constructor Summary

Constructors

Constructor and Description
AbstractRatingVectorPDAO(DataAccessObject dao)

Method Summary

Modifier and Type	Method and Description
protected abstract EntityType	getEntityType() Get the desired type of entities.
protected abstract Long2DoubleMap	makeVector(java.util.List<Entity> entities) Make a vector from entities.
ObjectStream<IdBox<Long2DoubleMap>>	streamUsers() Stream all users in the data set.
Long2DoubleMap	userRatingVector(long user) Get a user’s rating vector.

Methods inherited from class java.lang.Object

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

Field Detail

dao

protected final DataAccessObject dao

Constructor Detail

AbstractRatingVectorPDAO

public AbstractRatingVectorPDAO(DataAccessObject dao)

Method Detail

userRatingVector

@Nonnull
public Long2DoubleMap userRatingVector(long user)

Description copied from interface: RatingVectorPDAO

Get a user’s rating vector.

Specified by:

userRatingVector in interface RatingVectorPDAO

Parameters:

user - The rating vector summarizing a user’s historical preferences.

Returns:

The unnormmalized user rating vector. Will return an empty vector for nonexistent users.

getEntityType

protected abstract EntityType getEntityType()

Get the desired type of entities.

Returns:

The desired type of entities.

makeVector

protected abstract Long2DoubleMap makeVector(java.util.List<Entity> entities)

Make a vector from entities.

Parameters:

entities - The entities.

Returns:

The vector.

streamUsers

public ObjectStream<IdBox<Long2DoubleMap>> streamUsers()

Description copied from interface: RatingVectorPDAO

Stream all users in the data set.

Specified by:

streamUsers in interface RatingVectorPDAO

Returns:

A stream over the users in the data set.