org.eclipse.rdf4j.model.util

Class Literals

java.lang.Object

org.eclipse.rdf4j.model.util.Literals

public class Literals
extends Object

Various utility methods related to Literal.

Author:

Arjohn Kampman, Peter Ansell

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Literals()

Method Summary

Modifier and Type	Method and Description
static boolean	canCreateLiteral(Object object) Deprecated. since 3.5.0
static Literal	createLiteral(ValueFactory valueFactory, Object object) Deprecated. since 3.5.0 - use Values.literal(Object) instead.
static Literal	createLiteralOrFail(ValueFactory valueFactory, Object object) Deprecated. since 3.5.0 - use Values.literal(Object, boolean) instead.
static boolean	getBooleanValue(Literal l, boolean fallback) Gets the boolean value of the supplied literal.
static boolean	getBooleanValue(Value v, boolean fallback) Returns the result of getBooleanValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.
static byte	getByteValue(Literal l, byte fallback) Gets the byte value of the supplied literal.
static byte	getByteValue(Value v, byte fallback) Returns the result of getByteValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.
static XMLGregorianCalendar	getCalendarValue(Literal l, XMLGregorianCalendar fallback) Gets the calendar value of the supplied literal.
static XMLGregorianCalendar	getCalendarValue(Value v, XMLGregorianCalendar fallback) Returns the result of getCalendarValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.
static BigDecimal	getDecimalValue(Literal l, BigDecimal fallback) Gets the decimal value of the supplied literal.
static BigDecimal	getDecimalValue(Value v, BigDecimal fallback) Returns the result of getDecimalValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.
static double	getDoubleValue(Literal l, double fallback) Gets the double value of the supplied literal.
static double	getDoubleValue(Value v, double fallback) Returns the result of getDoubleValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.
static Duration	getDurationValue(Literal l, Duration fallback) Gets the Duration value of the supplied literal.
static float	getFloatValue(Literal l, float fallback) Gets the float value of the supplied literal.
static float	getFloatValue(Value v, float fallback) Returns the result of getFloatValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.
static BigInteger	getIntegerValue(Literal l, BigInteger fallback) Gets the integer value of the supplied literal.
static BigInteger	getIntegerValue(Value v, BigInteger fallback) Returns the result of getIntegerValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.
static int	getIntValue(Literal l, int fallback) Gets the int value of the supplied literal.
static int	getIntValue(Value v, int fallback) Returns the result of getIntValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.
static String	getLabel(Literal l, String fallback) Gets the label of the supplied literal.
static String	getLabel(Optional v, String fallback)
static String	getLabel(Value v, String fallback) Returns the result of getLabel((Literal)v, fallback in case the supplied value is a literal, returns the fallback value otherwise.
static long	getLongValue(Literal l, long fallback) Gets the long value of the supplied literal.
static long	getLongValue(Value v, long fallback) Returns the result of getLongValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.
static short	getShortValue(Literal l, short fallback) Gets the short value of the supplied literal.
static short	getShortValue(Value v, short fallback) Returns the result of getShortValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.
static Optional<XSD.Datatype>	getXsdDatatype(Literal l) Retrieves the XSD.Datatype value for the supplied Literal, if it has one.
static boolean	isLanguageLiteral(Literal literal) Helper method to determine whether a literal is a language literal, and not a typed literal.
static boolean	isValidLanguageTag(String languageTag) Checks if the given string is a BCP47 language tag according to the rules defined by the JDK in the Locale API.
static boolean	langMatches(String langTag, String langRange) Implements language range filtering for SPARQL langMatches (https://www.w3.org/TR/sparql11-query/#func-langMatches).
static String	normalizeLanguageTag(String languageTag) Normalizes the given BCP47 language tag according to the rules defined by the JDK in the Locale API.

Methods inherited from class java.lang.Object

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

Constructor Detail

Literals

protected Literals()

Method Detail

getLabel

public static String getLabel(Literal l,
                              String fallback)

Gets the label of the supplied literal. The fallback value is returned in case the supplied literal is null.

Parameters:

l - The literal to get the label for.

fallback - The value to fall back to in case the supplied literal is null.

Returns:

Either the literal's label, or the fallback value.

getLabel

public static String getLabel(Value v,
                              String fallback)

Returns the result of getLabel((Literal)v, fallback in case the supplied value is a literal, returns the fallback value otherwise.

getLabel

public static String getLabel(Optional v,
                              String fallback)

getXsdDatatype

public static Optional<XSD.Datatype> getXsdDatatype(Literal l)

Retrieves the XSD.Datatype value for the supplied Literal, if it has one.

Parameters:

a - Literal

Returns:

an Optional XSD.Datatype enum, if one is available. Note that the absence of this enum does not indicate that the literal has no datatype, merely that it has no cached enum representation of that datatype.

Since:

3.5.0

getByteValue

public static byte getByteValue(Literal l,
                                byte fallback)

Gets the byte value of the supplied literal. The fallback value is returned in case Literal.byteValue() throws a NumberFormatException.

Parameters:

l - The literal to get the byte value for.

fallback - The value to fall back to in case no byte value could gotten from the literal.

Returns:

Either the literal's byte value, or the fallback value.

getByteValue

public static byte getByteValue(Value v,
                                byte fallback)

Returns the result of getByteValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.

getShortValue

public static short getShortValue(Literal l,
                                  short fallback)

Gets the short value of the supplied literal. The fallback value is returned in case Literal.shortValue() throws a NumberFormatException.

Parameters:

l - The literal to get the short value for.

fallback - The value to fall back to in case no short value could gotten from the literal.

Returns:

Either the literal's short value, or the fallback value.

getShortValue

public static short getShortValue(Value v,
                                  short fallback)

Returns the result of getShortValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.

getIntValue

public static int getIntValue(Literal l,
                              int fallback)

Gets the int value of the supplied literal. The fallback value is returned in case Literal.intValue() throws a NumberFormatException.

Parameters:

l - The literal to get the int value for.

fallback - The value to fall back to in case no int value could gotten from the literal.

Returns:

Either the literal's int value, or the fallback value.

getIntValue

public static int getIntValue(Value v,
                              int fallback)

Returns the result of getIntValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.

getLongValue

public static long getLongValue(Literal l,
                                long fallback)

Gets the long value of the supplied literal. The fallback value is returned in case Literal.longValue() throws a NumberFormatException.

Parameters:

l - The literal to get the long value for.

fallback - The value to fall back to in case no long value could gotten from the literal.

Returns:

Either the literal's long value, or the fallback value.

getLongValue

public static long getLongValue(Value v,
                                long fallback)

Returns the result of getLongValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.

getIntegerValue

public static BigInteger getIntegerValue(Literal l,
                                         BigInteger fallback)

Gets the integer value of the supplied literal. The fallback value is returned in case Literal.integerValue() throws a NumberFormatException.

Parameters:

l - The literal to get the integer value for.

fallback - The value to fall back to in case no integer value could gotten from the literal.

Returns:

Either the literal's integer value, or the fallback value.

getIntegerValue

public static BigInteger getIntegerValue(Value v,
                                         BigInteger fallback)

Returns the result of getIntegerValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.

getDecimalValue

public static BigDecimal getDecimalValue(Literal l,
                                         BigDecimal fallback)

Gets the decimal value of the supplied literal. The fallback value is returned in case Literal.decimalValue() throws a NumberFormatException.

Parameters:

l - The literal to get the decimal value for.

fallback - The value to fall back to in case no decimal value could gotten from the literal.

Returns:

Either the literal's decimal value, or the fallback value.

getDecimalValue

public static BigDecimal getDecimalValue(Value v,
                                         BigDecimal fallback)

Returns the result of getDecimalValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.

getFloatValue

public static float getFloatValue(Literal l,
                                  float fallback)

Gets the float value of the supplied literal. The fallback value is returned in case Literal.floatValue() throws a NumberFormatException.

Parameters:

l - The literal to get the float value for.

fallback - The value to fall back to in case no float value could gotten from the literal.

Returns:

Either the literal's float value, or the fallback value.

getFloatValue

public static float getFloatValue(Value v,
                                  float fallback)

Returns the result of getFloatValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.

getDoubleValue

public static double getDoubleValue(Literal l,
                                    double fallback)

Gets the double value of the supplied literal. The fallback value is returned in case Literal.doubleValue() throws a NumberFormatException.

Parameters:

l - The literal to get the double value for.

fallback - The value to fall back to in case no double value could gotten from the literal.

Returns:

Either the literal's double value, or the fallback value.

getDoubleValue

public static double getDoubleValue(Value v,
                                    double fallback)

Returns the result of getDoubleValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.

getBooleanValue

public static boolean getBooleanValue(Literal l,
                                      boolean fallback)

Gets the boolean value of the supplied literal. The fallback value is returned in case Literal.booleanValue() throws a NumberFormatException.

Parameters:

l - The literal to get the boolean value for.

fallback - The value to fall back to in case no boolean value could gotten from the literal.

Returns:

Either the literal's boolean value, or the fallback value.

getBooleanValue

public static boolean getBooleanValue(Value v,
                                      boolean fallback)

Returns the result of getBooleanValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.

getCalendarValue

public static XMLGregorianCalendar getCalendarValue(Literal l,
                                                    XMLGregorianCalendar fallback)

Gets the calendar value of the supplied literal. The fallback value is returned in case Literal.calendarValue() throws a NumberFormatException.

Parameters:

l - The literal to get the calendar value for.

fallback - The value to fall back to in case no calendar value could gotten from the literal.

Returns:

Either the literal's calendar value, or the fallback value.

getDurationValue

public static Duration getDurationValue(Literal l,
                                        Duration fallback)

Gets the Duration value of the supplied literal. The fallback value is returned in case XMLDatatypeUtil.parseDuration(String) throws an exception.

Parameters:

l - The literal to get the Duration value for.

fallback - The value to fall back to in case no Duration value could gotten from the literal.

Returns:

Either the literal's Duration value, or the fallback value.

getCalendarValue

public static XMLGregorianCalendar getCalendarValue(Value v,
                                                    XMLGregorianCalendar fallback)

Returns the result of getCalendarValue((Literal)value, fallback) in case the supplied value is a literal, returns the fallback value otherwise.

createLiteral

@Deprecated
public static Literal createLiteral(ValueFactory valueFactory,
                                                Object object)

Deprecated. since 3.5.0 - use Values.literal(Object) instead.

Creates a typed Literal out of the supplied object, mapping the runtime type of the object to the appropriate XML Schema type. If no mapping is available, the method returns a literal with the string representation of the supplied object as the value, and XSD.STRING as the datatype. Recognized types are Boolean, Byte, Double, Float, Integer, Long, Short, XMLGregorianCalendar , and Date.

Parameters:

valueFactory -

object - an object to be converted to a typed literal.

Returns:

a typed literal representation of the supplied object.

Throws:

NullPointerException - If the object was null.

createLiteralOrFail

@Deprecated
public static Literal createLiteralOrFail(ValueFactory valueFactory,
                                                      Object object)
                                               throws LiteralUtilException

Deprecated. since 3.5.0 - use Values.literal(Object, boolean) instead.

Creates a typed Literal out of the supplied object, mapping the runtime type of the object to the appropriate XML Schema type. If no mapping is available, the method throws a LiteralUtilException. Recognized types are Boolean, Byte, Double, Float, Integer, Long, Short, XMLGregorianCalendar , and Date.

Parameters:

valueFactory -

object - an object to be converted to a typed literal.

Returns:

a typed literal representation of the supplied object.

Throws:

LiteralUtilException - If the literal could not be created.

NullPointerException - If the object was null.

canCreateLiteral

@Deprecated
public static boolean canCreateLiteral(Object object)

Deprecated. since 3.5.0

Helper method for determining whether a literal could be created from an object using a ValueFactory.

Parameters:

object - an object to check for the possibility of being converted to a typed literal.

Returns:

True if a literal could be created from the given object, based solely on its type and the methods available on the ValueFactory interface and false otherwise. Returns false if the object is null.

isLanguageLiteral

public static boolean isLanguageLiteral(Literal literal)

Helper method to determine whether a literal is a language literal, and not a typed literal.

Parameters:

literal - The literal to check

Returns:

True if the literal has a language tag attached to it and false otherwise.

normalizeLanguageTag

public static String normalizeLanguageTag(String languageTag)
                                   throws IllformedLocaleException

Normalizes the given BCP47 language tag according to the rules defined by the JDK in the Locale API.

Parameters:

languageTag - An unnormalized, valid, language tag

Returns:

A normalized version of the given language tag

Throws:

IllformedLocaleException - If the given language tag is ill-formed according to the rules specified in BCP47.

isValidLanguageTag

public static boolean isValidLanguageTag(String languageTag)

Checks if the given string is a BCP47 language tag according to the rules defined by the JDK in the Locale API.

Parameters:

languageTag - A language tag

Returns:

true if the given language tag is well-formed according to the rules specified in BCP47.

langMatches

public static boolean langMatches(String langTag,
                                  String langRange)

Implements language range filtering for SPARQL langMatches (https://www.w3.org/TR/sparql11-query/#func-langMatches).

Parameters:

langTag - the tag to filter

langRange - the range to filter against

Returns:

true if langTag matches langRange