es.uam.eps.ir.ranksys.fast.preference

Class AbstractFastPreferenceData<U,I>

java.lang.Object

es.uam.eps.ir.ranksys.fast.preference.AbstractFastPreferenceData<U,I>

Type Parameters:

U - type of the users

I - type of the items

All Implemented Interfaces:

ItemIndex<I>, UserIndex<U>, PreferenceData<U,I>, FastItemIndex<I>, FastUserIndex<U>, FastPreferenceData<U,I>, Serializable

Direct Known Subclasses:

IteratorsAbstractFastPreferenceData, StreamsAbstractFastPreferenceData

public abstract class AbstractFastPreferenceData<U,I>
extends Object
implements FastPreferenceData<U,I>, Serializable

Abstract FastFeatureData, implementing the interfaces of FastUserIndex and FastItemIndex by delegating to implementations of these.

Author:

Saúl Vargas (saul.vargas@uam.es)

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected FastItemIndex<I>	ii item index.
protected Function<IdxPref,IdPref<U>>	iPrefFun Converter from IdxPref to IdPref (preference from user).
protected FastUserIndex<U>	ui user index.
protected Function<IdxPref,IdPref<I>>	uPrefFun Converter from IdxPref to IdPref (preference for item).

Constructor Summary

Constructors

Constructor and Description
AbstractFastPreferenceData(FastUserIndex<U> users, FastItemIndex<I> items) Constructor.
AbstractFastPreferenceData(FastUserIndex<U> userIndex, FastItemIndex<I> itemIndex, Function<IdxPref,IdPref<I>> uPrefFun, Function<IdxPref,IdPref<U>> iPrefFun) Constructor.

Method Summary

Modifier and Type	Method and Description
boolean	containsItem(I i) Checks whether the index contains an item.
boolean	containsUser(U u) Checks whether the index contains a user.
Stream<I>	getAllItems() Retrieves a stream of the indexed items.
Stream<U>	getAllUsers() Retrieves a stream of the indexed users.
Stream<? extends IdPref<U>>	getItemPreferences(I i) Returns a stream of the preferences of the item
Stream<I>	getItemsWithPreferences() Returns a stream of the items with preferences
Stream<? extends IdPref<I>>	getUserPreferences(U u) Returns a stream of the preferences of the user
Stream<U>	getUsersWithPreferences() Returns a stream of the users with preferences
I	iidx2item(int i) Returns the item represented with the index.
int	item2iidx(I i) Returns the index assigned to the item.
int	numItems() Counts the number of indexed items.
int	numItems(U u) Returns the number of items with preference for user u
int	numItemsWithPreferences() Returns the number of items with preferences.
int	numUsers() Counts the number of indexed users.
int	numUsers(I i) Returns the number of users with preference for item i
int	numUsersWithPreferences() Returns the number of users with preferences.
U	uidx2user(int i) Returns the user represented with the index.
int	user2uidx(U u) Returns the index assigned to the user.

Methods inherited from class java.lang.Object

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

Methods inherited from interface es.uam.eps.ir.ranksys.fast.preference.FastPreferenceData

getIidxPreferences, getIidxUidxs, getIidxVs, getIidxWithPreferences, getUidxIidxs, getUidxPreferences, getUidxVs, getUidxWithPreferences, numItems, numUsers, useIteratorsPreferentially

Methods inherited from interface es.uam.eps.ir.ranksys.core.preference.PreferenceData

numPreferences

Methods inherited from interface es.uam.eps.ir.ranksys.fast.index.FastUserIndex

getAllUidx, uidx2user, uidx2user, user2uidx, user2uidx

Methods inherited from interface es.uam.eps.ir.ranksys.fast.index.FastItemIndex

getAllIidx, iidx2item, iidx2item, item2iidx, item2iidx

Field Detail

ui

protected final FastUserIndex<U> ui

user index.

ii

protected final FastItemIndex<I> ii

item index.

uPrefFun

protected final Function<IdxPref,IdPref<I>> uPrefFun

Converter from IdxPref to IdPref (preference for item).

iPrefFun

protected final Function<IdxPref,IdPref<U>> iPrefFun

Converter from IdxPref to IdPref (preference from user).

Constructor Detail

AbstractFastPreferenceData

public AbstractFastPreferenceData(FastUserIndex<U> users,
                                  FastItemIndex<I> items)

Constructor.

Parameters:

users - user index

items - item index

AbstractFastPreferenceData

public AbstractFastPreferenceData(FastUserIndex<U> userIndex,
                                  FastItemIndex<I> itemIndex,
                                  Function<IdxPref,IdPref<I>> uPrefFun,
                                  Function<IdxPref,IdPref<U>> iPrefFun)

Constructor.

Parameters:

userIndex - user index

itemIndex - item index

uPrefFun - converter from IdxPref to IdPref (preference for item).

iPrefFun - converter from IdxPref to IdPref (preference from user).

Method Detail

user2uidx

public int user2uidx(U u)

Description copied from interface: FastUserIndex

Returns the index assigned to the user.

Specified by:

user2uidx in interface FastUserIndex<U>

Parameters:

u - user

Returns:

the index of the user, or -1 if the user does not exist

uidx2user

public U uidx2user(int i)

Description copied from interface: FastUserIndex

Returns the user represented with the index.

Specified by:

uidx2user in interface FastUserIndex<U>

Parameters:

i - user index

Returns:

the user whose index is uidx

containsUser

public boolean containsUser(U u)

Description copied from interface: UserIndex

Checks whether the index contains a user.

Specified by:

containsUser in interface UserIndex<U>

Specified by:

containsUser in interface FastUserIndex<U>

Parameters:

u - user

Returns:

true if the index contains the user, false otherwise

numUsers

public int numUsers()

Description copied from interface: UserIndex

Counts the number of indexed users.

Specified by:

numUsers in interface UserIndex<U>

Returns:

the total number of users

getAllUsers

public Stream<U> getAllUsers()

Description copied from interface: UserIndex

Retrieves a stream of the indexed users.

Specified by:

getAllUsers in interface UserIndex<U>

Specified by:

getAllUsers in interface FastUserIndex<U>

Returns:

a stream of all the users

item2iidx

public int item2iidx(I i)

Description copied from interface: FastItemIndex

Returns the index assigned to the item.

Specified by:

item2iidx in interface FastItemIndex<I>

Parameters:

i - item

Returns:

the index of the item, or -1 if the item does not exist

iidx2item

public I iidx2item(int i)

Description copied from interface: FastItemIndex

Returns the item represented with the index.

Specified by:

iidx2item in interface FastItemIndex<I>

Parameters:

i - item index

Returns:

the item whose index is iidx

containsItem

public boolean containsItem(I i)

Description copied from interface: ItemIndex

Checks whether the index contains an item.

Specified by:

containsItem in interface ItemIndex<I>

Specified by:

containsItem in interface FastItemIndex<I>

Parameters:

i - item

Returns:

true if the index contains the item, false otherwise

numItems

public int numItems()

Description copied from interface: ItemIndex

Counts the number of indexed items.

Specified by:

numItems in interface ItemIndex<I>

Returns:

the total number of item

getAllItems

public Stream<I> getAllItems()

Description copied from interface: ItemIndex

Retrieves a stream of the indexed items.

Specified by:

getAllItems in interface ItemIndex<I>

Specified by:

getAllItems in interface FastItemIndex<I>

Returns:

a stream of all the items

numUsers

public int numUsers(I i)

Description copied from interface: PreferenceData

Returns the number of users with preference for item i

Specified by:

numUsers in interface PreferenceData<U,I>

Parameters:

i - item

Returns:

number of users with preferences for item i

numItems

public int numItems(U u)

Description copied from interface: PreferenceData

Returns the number of items with preference for user u

Specified by:

numItems in interface PreferenceData<U,I>

Parameters:

u - user

Returns:

number of items with preferences for user u

getUserPreferences

public Stream<? extends IdPref<I>> getUserPreferences(U u)

Description copied from interface: PreferenceData

Returns a stream of the preferences of the user

Specified by:

getUserPreferences in interface PreferenceData<U,I>

Parameters:

u - user

Returns:

stream of preferences

getItemPreferences

public Stream<? extends IdPref<U>> getItemPreferences(I i)

Description copied from interface: PreferenceData

Returns a stream of the preferences of the item

Specified by:

getItemPreferences in interface PreferenceData<U,I>

Parameters:

i - item

Returns:

stream of preferences

getUsersWithPreferences

public Stream<U> getUsersWithPreferences()

Description copied from interface: PreferenceData

Returns a stream of the users with preferences

Specified by:

getUsersWithPreferences in interface PreferenceData<U,I>

Returns:

stream of users with preferences

getItemsWithPreferences

public Stream<I> getItemsWithPreferences()

Description copied from interface: PreferenceData

Returns a stream of the items with preferences

Specified by:

getItemsWithPreferences in interface PreferenceData<U,I>

Returns:

stream of items with preferences

numUsersWithPreferences

public int numUsersWithPreferences()

Description copied from interface: PreferenceData

Returns the number of users with preferences.

Specified by:

numUsersWithPreferences in interface PreferenceData<U,I>

Returns:

number of users with preferences

numItemsWithPreferences

public int numItemsWithPreferences()

Description copied from interface: PreferenceData

Returns the number of items with preferences.

Specified by:

numItemsWithPreferences in interface PreferenceData<U,I>

Returns:

number of items with preferences