es.upm.etsisi.cf4j.data

Class User

java.lang.Object

es.upm.etsisi.cf4j.data.User

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

TestUser

public class User
extends Object
implements Serializable

Defines a composition of an User. An user is composed by:

• User unique identifier.
• User index in the DataModel which stores him or her.
• Array of items rated by the user.

It is not recommended that developers generate new instances of this class since this is a memory-structural class.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected double	average Average (training) rating
protected DataBank	dataBank DataBank to store heterogeneous information
protected String	id User unique identifier
protected SortedRatingList	itemsRatings Items rated by the user
protected double	max Maximum (training) rating value
protected double	min Minimum (training) rating value
protected int	userIndex User index in the DataModel

Constructor Summary

Constructors

Constructor and Description
User(String id, int index) Creates a new instance of an user.

Method Summary

Modifier and Type	Method and Description
void	addRating(int itemIndex, double rating) Adds a new rating of the user to an item.
int	findItem(int itemIndex) Finds position of a user's rating given the index of the Item in the DataModel.
DataBank	getDataBank() Gets the DataBank instance that stores heterogeneous information related to the User.
String	getId() Returns the user unique identifier
int	getItemAt(int pos) Returns the index of the Item rated by the User at the given position.
double	getMaxRating() Gets the maximum rating of the user
double	getMinRating() Gets the minimum rating of the user
int	getNumberOfRatings() Gets the number of items rated by the user
double	getRatingAt(int pos) Returns the rating of the user to the item at the pos position
double	getRatingAverage() Gets the average value of ratings
int	getUserIndex() Return the user index inside the DataModel

Methods inherited from class java.lang.Object

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

Field Detail

id

protected String id

User unique identifier

userIndex

protected int userIndex

User index in the DataModel

min

protected double min

Minimum (training) rating value

max

protected double max

Maximum (training) rating value

average

protected double average

Average (training) rating

dataBank

protected DataBank dataBank

DataBank to store heterogeneous information

itemsRatings

protected SortedRatingList itemsRatings

Items rated by the user

Constructor Detail

User

public User(String id,
            int index)

Creates a new instance of an user. This constructor should not be used by developers.

Parameters:

id - User unique identifier

index - Index of the user in the Users' array of the DataModel

Method Detail

getDataBank

public DataBank getDataBank()

Gets the DataBank instance that stores heterogeneous information related to the User.

Returns:

DataBank instance

getId

public String getId()

Returns the user unique identifier

Returns:

User identifier

getUserIndex

public int getUserIndex()

Return the user index inside the DataModel

Returns:

User index inside the DataModel

getItemAt

public int getItemAt(int pos)

Returns the index of the Item rated by the User at the given position.

Parameters:

pos - Position

Returns:

Index of the item in the Items' array of the DataModel

getRatingAt

public double getRatingAt(int pos)

Returns the rating of the user to the item at the pos position

Parameters:

pos - Position

Returns:

Rating at indicated position

findItem

public int findItem(int itemIndex)

Finds position of a user's rating given the index of the Item in the DataModel.

Parameters:

itemIndex - Item index

Returns:

Item position if the item has been rated by the user or -1 if do not

getNumberOfRatings

public int getNumberOfRatings()

Gets the number of items rated by the user

Returns:

Number of ratings

addRating

public void addRating(int itemIndex,
                      double rating)

Adds a new rating of the user to an item. You cannot overwrite an existing rating, otherwise this method will throws an IllegalArgumentException. It is not recommended to use this method, use DataModel.addRating(...) instead.

Parameters:

itemIndex - Item index which identifies an item in the DataModel

rating - Rating value

getMinRating

public double getMinRating()

Gets the minimum rating of the user

Returns:

Minimum rating

getMaxRating

public double getMaxRating()

Gets the maximum rating of the user

Returns:

Maximum rating

getRatingAverage

public double getRatingAverage()

Gets the average value of ratings

Returns:

Rating average