zorba::DynamicContext Class Reference

Instances of the class DynamicContext contain the information that is available at the time the query is executed. More...

#include <zorba/dynamic_context.h>

List of all members.

Public Member Functions
virtual Item	getCurrentDateTime ()=0
	Retrieve the dateTime Item used at the time the query is executed (see setCurrentDateTime()).
virtual Item	getDefaultCollection ()=0
	Return the value of the default collection that is used when calling the fn:collection function without a parameter.
virtual int	getImplicitTimezone ()=0
	Retrieve the implicit timezone used in comparisons or arithmetic operations of date, time, or dateTime values.
virtual bool	setContextItem (const Item &aItem)=0
	Defines the context item.
virtual bool	setContextItemAsDocument (const String &aDocURI)=0
	Defines the context item and assigns it the document downloaded from Uri.
virtual bool	setContextItemAsDocument (const String &aDocURI, std::auto_ptr< std::istream > aDocStream)=0
	Defines the context item and assigns it the document that results from parsing the given input stream.
virtual bool	setCurrentDateTime (const Item &aDateTimeItem)=0
	Defines the value of the current date time that can be accessed by the fn:current-dateTime() function at the time the query is executed.
virtual bool	setDefaultCollection (const Item &aCollectionUri)=0
	Defines the value of the default collection that is used when calling the fn:collection function without a parameter.
virtual bool	setImplicitTimezone (int aTimezone)=0
	Defines the variable of the implicit timezone to be used when a date, time, or dateTime value that does not have a timezone is used in a comparison or arithmetic operation.
virtual bool	setVariable (const String &aQName, const ResultIterator_t &aResultIterator)=0
	Defines the external variable identifies by aQName and assigns it the sequence that is returned by evaluating aResultIterator.
virtual bool	setVariable (const String &aQName, const Item &aItem)=0
	Defines the external variable identified by aQName and assigns it the value of aItem.
virtual bool	setVariableAsDocument (const String &aQName, const String &xml_uri)=0
	Defines the external variable identifies by aQName and assigns it the the document downloaded from Uri.
virtual bool	setVariableAsDocument (const String &aQName, const String &aDocURI, std::auto_ptr< std::istream > aDocStream)=0
	Defines the external variable identifies by aQName and assigns it the the document that results from reading and parsing the given istream.
Protected Member Functions
virtual	~DynamicContext ()
	Destructor.

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Detailed Description

Instances of the class DynamicContext contain the information that is available at the time the query is executed.

The class contains the information that is defined in the XQuery specification (see http://www.w3.org/TR/xquery/#eval_context).

A dynamic context always belongs to a particular query and, hence, can be retrieved by calling getDynamicContext on a compiled query (see XQuery::getDynamicContext()).

Examples:

context.cpp, and simple.cpp.

Definition at line 38 of file dynamic_context.h.

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Constructor & Destructor Documentation

virtual zorba::DynamicContext::~DynamicContext

(

)

[inline, protected, virtual]

Destructor.

Definition at line 188 of file dynamic_context.h.

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Member Function Documentation

virtual Item zorba::DynamicContext::getCurrentDateTime

(

)

[pure virtual]

Retrieve the dateTime Item used at the time the query is executed (see setCurrentDateTime()).

Returns:

Item the dateTime Item used at the time the query is executed.

virtual Item zorba::DynamicContext::getDefaultCollection

(

)

[pure virtual]

Return the value of the default collection that is used when calling the fn:collection function without a parameter.

Returns:

Item the default collection that is set in this dynamic context.

Exceptions:

ZorbaException

if an error occured.

virtual int zorba::DynamicContext::getImplicitTimezone

(

)

[pure virtual]

Retrieve the implicit timezone used in comparisons or arithmetic operations of date, time, or dateTime values.

Returns:

int the implicit timezone. Note that 0 is returned if an error occured and an ErrorHandler is used.

Exceptions:

ZorbaException

if an error occured.

virtual bool zorba::DynamicContext::setContextItem

(

const Item &

aItem

)

[pure virtual]

Defines the context item.

Parameters:

aItem

the Item that is used as value for the context item.

Returns:

true if the context item was set, false otherwise.

Exceptions:

ZorbaException

if an error occured (e.g. the given Item is not valid).

Examples:

context.cpp.

virtual bool zorba::DynamicContext::setContextItemAsDocument

(

const String &

aDocURI

)

[pure virtual]

Defines the context item and assigns it the document downloaded from Uri.

Parameters:

	aDocURI	the source Uri and the URI that is used to reference the document in the XmlDataManager.
	aDocStream	the istream used to read the document from. Ownership of the input stream is transfered to the processor using an auto_ptr.

Exceptions:

ZorbaException

if an error occured (e.g. the input document could not be parsed).

virtual bool zorba::DynamicContext::setContextItemAsDocument	(	const String &	aDocURI,
		std::auto_ptr< std::istream >	aDocStream
	)			[pure virtual]

Defines the context item and assigns it the document that results from parsing the given input stream.

Parameters:

	aDocURI	the URI that is used to reference the document in the XmlDataManager.
	aDocStream	the istream used to read the document from. Ownership of the input stream is transfered to the processor using an auto_ptr.

Exceptions:

ZorbaException

if an error occured (e.g. the input document could not be parsed).

Examples:

context.cpp.

virtual bool zorba::DynamicContext::setCurrentDateTime

(

const Item &

aDateTimeItem

)

[pure virtual]

Defines the value of the current date time that can be accessed by the fn:current-dateTime() function at the time the query is executed.

If the current date time has not been set explicitly the value of the date and time is used at the time the query is created or cloned, respectively.

Parameters:

aDateTimeItem

the dateTime Item.

Returns:

true if the variable has been set successfully, false otherwise.

Exceptions:

ZorbaException

if an error occured (e.g. the given Item is invalid or not a Item of type dateTime

Examples:

context.cpp.

virtual bool zorba::DynamicContext::setDefaultCollection

(

const Item &

aCollectionUri

)

[pure virtual]

Defines the value of the default collection that is used when calling the fn:collection function without a parameter.

Parameters:

aCollectionUri

the URI of the collection used by the fn:collection function.

Returns:

true if the default collection has been set successfully, false otherwise.

Exceptions:

ZorbaException

if an error occured.

virtual bool zorba::DynamicContext::setImplicitTimezone

(

int

aTimezone

)

[pure virtual]

Defines the variable of the implicit timezone to be used when a date, time, or dateTime value that does not have a timezone is used in a comparison or arithmetic operation.

Parameters:

aTimezone

the implicit timezone as int that should be used.

Returns:

true if the implicit timezone has been set successfully, false otherwise.

Exceptions:

ZorbaException

if an error occured.

virtual bool zorba::DynamicContext::setVariable	(	const String &	aQName,
		const ResultIterator_t &	aResultIterator
	)			[pure virtual]

Defines the external variable identifies by aQName and assigns it the sequence that is returned by evaluating aResultIterator.

Parameters:

	aQName	the QName that identifies the external variable.
	aResultIterator	the ResultIterator producing the sequence that is assigned to the variable.

Returns:

true if the variable has been set successfully, false otherwise.

Exceptions:

ZorbaException

if an error occured (e.g. the given ResultIterator is not valid).

virtual bool zorba::DynamicContext::setVariable	(	const String &	aQName,
		const Item &	aItem
	)			[pure virtual]

Defines the external variable identified by aQName and assigns it the value of aItem.

Parameters:

	aQName	the QName that identifies the external variable.
	aItem	the Item that is used as value for the variable.

Returns:

true if the variable has been set, false otherwise.

Exceptions:

ZorbaException

if an error occured (e.g. the given Item is not valid).

Examples:

context.cpp, and simple.cpp.

virtual bool zorba::DynamicContext::setVariableAsDocument	(	const String &	aQName,
		const String &	xml_uri
	)			[pure virtual]

Defines the external variable identifies by aQName and assigns it the the document downloaded from Uri.

Parameters:

	aQName	the QName that identifies the external variable.
	aDocURI	the source Uri and the URI that is used to reference the document in the XmlDataManager.

Returns:

true if the variable has been set successfully, false otherwise.

Exceptions:

ZorbaException

if an error occured (e.g. the given ResultIterator is not valid).

virtual bool zorba::DynamicContext::setVariableAsDocument	(	const String &	aQName,
		const String &	aDocURI,
		std::auto_ptr< std::istream >	aDocStream
	)			[pure virtual]

Defines the external variable identifies by aQName and assigns it the the document that results from reading and parsing the given istream.

Parameters:

	aQName	the QName that identifies the external variable.
	aDocURI	the URI that is used to reference the document in the XmlDataManager.
	aDocStream	the istream used to read the document from. Ownership of the input stream is transfered to the processor using an auto_ptr.

Returns:

true if the variable has been set successfully, false otherwise.

Exceptions:

ZorbaException

if an error occured (e.g. the given ResultIterator is not valid).

Examples:

context.cpp.

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The documentation for this class was generated from the following file:

• dynamic_context.h