LiteralValue Class Reference
from PyKDE4.soprano import *
Namespace: Soprano.LiteralValue
Detailed Description
\class LiteralValue literalvalue.h Soprano/LiteralValue
Represents a literal value of an RDF Node.
LiteralValue is based on QVariant to support
a subset of the XML Schema types that are compatible
with QT types.
The following types are supported natively including
automatic type conversion. Other types are represented
as strings.
int (Vocabulary.XMLSchema.xsdInt)
qlonglong (Vocabulary.XMLSchema.xsdLong)
unsigned int (Vocabulary.XMLSchema.unsignedInt)
qulonglong (Vocabulary.XMLSchema.unsignedLong)
bool (Vocabulary.XMLSchema.boolean)
double and float (Vocabulary.XMLSchema.xsdDouble) (float values are always converted to double)
QString (Vocabulary.XMLSchema.string or Vocabulary.RDF.XMLLiteral)
QDate (Vocabulary.XMLSchema.date)
QTime (Vocabulary.XMLSchema.time)
QDateTime (Vocabulary.XMLSchema.dateTime)
QByteArray (Vocabulary.XMLSchema.base64Binary)
Literal values can be converted from strings via fromString().
\sa Vocabulary.XMLSchema
- Author:
- Sebastian Trueg <trueg@kde.org>
Methods |
| __init__ (self) |
| __init__ (self, Soprano.LiteralValue other) |
| __init__ (self, QVariant v) |
| __init__ (self, long i) |
| __init__ (self, float d) |
| __init__ (self, QString string) |
| __init__ (self, QLatin1String string) |
| __init__ (self, QString string) |
| __init__ (self, QDate date) |
| __init__ (self, QTime time) |
| __init__ (self, QDateTime datetime) |
| __init__ (self, QByteArray data) |
Soprano.LiteralValue | createPlainLiteral (self, QString value, Soprano.LanguageTag lang=Soprano.LanguageTag()) |
QUrl | dataTypeUri (self) |
QUrl | dataTypeUriFromType (self, QVariant.Type type) |
Soprano.LiteralValue | fromString (self, QString value, QVariant.Type type) |
Soprano.LiteralValue | fromString (self, QString value, QUrl dataTypeUri) |
bool | isBool (self) |
bool | isByteArray (self) |
bool | isDate (self) |
bool | isDateTime (self) |
bool | isDouble (self) |
bool | isInt (self) |
bool | isInt64 (self) |
bool | isPlain (self) |
bool | isString (self) |
bool | isTime (self) |
bool | isUnsignedInt (self) |
bool | isUnsignedInt64 (self) |
bool | isValid (self) |
Soprano.LanguageTag | language (self) |
bool | operator != (self, Soprano.LiteralValue other) |
bool | operator == (self, Soprano.LiteralValue other) |
bool | toBool (self) |
QByteArray | toByteArray (self) |
QDate | toDate (self) |
QDateTime | toDateTime (self) |
float | toDouble (self) |
int | toInt (self) |
long | toInt64 (self) |
QString | toString (self) |
QTime | toTime (self) |
long | toUnsignedInt (self) |
long | toUnsignedInt64 (self) |
QVariant.Type | type (self) |
QVariant.Type | typeFromDataTypeUri (self, QUrl dataTypeUri) |
QVariant | variant (self) |
Method Documentation
__init__ |
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long |
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float |
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__init__ |
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QDate |
date |
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__init__ |
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QTime |
time |
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Create a plain LiteralValue object with an optional language tag.
- Parameters:
-
| value | The value of the literal.
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- Parameters:
-
Both an empty value and lang will result in an invalid LiteralValue
instance but an empty value with a valid lang is possible. A valid
value with an empty lang will result in a plain, untyped literal with no
language tag.
- Returns:
- A newly created LiteralValue instance based on the provided value and
lang.
QUrl dataTypeUri |
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self ) |
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The XML Schema datatype URI.
- Returns:
- The URI of the XML Schema type referring to the
stored type or an empty QUrl if the LiteralValue is empty or
is a plain literal.
Convert a QVariant.Type into an XML Schema URI.
- Returns:
- The XML Schema URI that corresponds to type or an empty QUrl if
the type os unknown, i.e. can not be mapped to an XML Schema type.
Create a LiteralValue object by parsing string value based on dataTypeUri.
- Parameters:
-
| value | The value of the literal. Might be converted based on dataTypeUri.
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- Parameters:
-
| dataTypeUri | The data type URI. %Soprano can automatically convert all XML schema
types. All other (unknown) types will be stored as a string value with the plain
dataTypeUri as type. Thus, unknown literal types can still be used without
automatic type conversion. (Be aware though, that changing the value of a LiteralValue
instance will reset the type, ie. custom data type URIs will be lost.)
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Both an empty value and dataTypeUri will result in an invalid LiteralValue
instance but an empty value with a valid dataTypeUri is possible. A valid
value with an invalid dataTypeUri will result in a LiteralValue of type
Vocabulary.XMLSchema.string.
- Returns:
- A newly created LiteralValue instance based on the provided value and
dataTypeUri.
\sa fromString(const QString&, QVariant.Type), Vocabulary.XMLSchema
Create a LiteralValue object by parsing string value based on dataTypeUri.
- Parameters:
-
| value | The value of the literal. Might be converted based on dataTypeUri.
|
- Parameters:
-
| dataTypeUri | The data type URI. %Soprano can automatically convert all XML schema
types. All other (unknown) types will be stored as a string value with the plain
dataTypeUri as type. Thus, unknown literal types can still be used without
automatic type conversion. (Be aware though, that changing the value of a LiteralValue
instance will reset the type, ie. custom data type URIs will be lost.)
|
Both an empty value and dataTypeUri will result in an invalid LiteralValue
instance but an empty value with a valid dataTypeUri is possible. A valid
value with an invalid dataTypeUri will result in a LiteralValue of type
Vocabulary.XMLSchema.string.
- Returns:
- A newly created LiteralValue instance based on the provided value and
dataTypeUri.
\sa fromString(const QString&, QVariant.Type), Vocabulary.XMLSchema
bool isByteArray |
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self ) |
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Determines if this literal value is a plain literal.
Plain literals have no data type, but may have an optional language tag.
- Returns:
- true if this literal is plain
Check if the literal contains a string value.
Be aware that unknown literal types are also
treated as strings. In that case compare
dataTypeUrl.
bool isUnsignedInt |
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self ) |
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bool isUnsignedInt64 |
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self ) |
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The language tag.
- Returns:
- The language tag of the plain literal or an empty LanguageTag
if the LiteralValue has no language or it is a typed literal.
Each type can be converted to a string which means that
toString in combination with dataTypeUrl provides all the
information necessary to store this literal as RDF.
The string value is cached so calling it multiple times in
a row is fast.
- Warning:
- For historical reasons this is not a user-readable representation.
\sa Node.toString
long toUnsignedInt |
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self ) |
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long toUnsignedInt64 |
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self ) |
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The type of the data.
- Returns:
- The QVariant type of the stored data or QVariant.Invalid
if it is an empty value.
Convert an XML Schema URI into a QVariant.Type.
- Returns:
- The QVariant.Type corresponding to dataTypeUri or QVariant.Invalid
if dataTypeUri is unknown.
The literal value represented in a QVariant.
Be aware that the RDF typing information is lost
in the converted variant.