net.sf.saxon.expr.instruct

Class GlobalContextRequirement

java.lang.Object

net.sf.saxon.expr.instruct.GlobalContextRequirement

public class GlobalContextRequirement
extends java.lang.Object

Information about the requirements placed by a query or stylesheet on the global context item: whether it is mandatory or optional, what its type must be, whether it is streamable, whether it has a default value. In XSLT, if more than one module specifies a global context item type, they must be the same. In XQuery, several modules can specify different required types, and the actual context item must satisfy them all.

Constructor Summary

Constructors

Constructor and Description
GlobalContextRequirement()

Method Summary

Modifier and Type	Method and Description
void	addRequiredItemType(ItemType requiredItemType) Specify the required item type of the context item
void	export(ExpressionPresenter out) Export the global context item declaration to an SEF export file
Expression	getDefaultValue() Get the expression that supplies the default value of the context item, if any.
ItemType	getRequiredItemType() Get the required item type of the context item.
java.util.List<ItemType>	getRequiredItemTypes() Get all the required item types.
boolean	isAbsentFocus() Ask whether the global context item for a query or stylesheet will be absent.
boolean	isExternal() Ask whether (in XQuery) the global context item is declared as external
boolean	isMayBeOmitted() Ask whether it is OK for the application to supply no context item
void	setAbsentFocus(boolean absent) Say whether the global context item for a query or stylesheet will be absent.
void	setDefaultValue(Expression defaultValue) Set the expression used to compute the default value of the global context item
void	setExternal(boolean external) Say whether (in XQuery) the global context item is declared as external
void	setMayBeOmitted(boolean mayOmit) Say whether it is OK for the application to supply no context item

Methods inherited from class java.lang.Object

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

Constructor Detail

GlobalContextRequirement

public GlobalContextRequirement()

Method Detail

getRequiredItemType

public ItemType getRequiredItemType()

Get the required item type of the context item. If several required item types have been registered (which only happens in XQuery with multiple modules) then this returns the first.

Returns:

The first registered required item type

getRequiredItemTypes

public java.util.List<ItemType> getRequiredItemTypes()

Get all the required item types. In XSLT there can only be one, but in XQuery there can be several, one for each module (the actual context item must satisfy them all)

Returns:

the list of required item types

addRequiredItemType

public void addRequiredItemType(ItemType requiredItemType)

Specify the required item type of the context item

Parameters:

requiredItemType - the required item type

getDefaultValue

public Expression getDefaultValue()

Get the expression that supplies the default value of the context item, if any. This is used only in XQuery.

Returns:

the expression used to compute the value of the context item, in the absence of an externally-supplied value

setDefaultValue

public void setDefaultValue(Expression defaultValue)

Set the expression used to compute the default value of the global context item

Parameters:

defaultValue - the expression used to compute the default value.

export

public void export(ExpressionPresenter out)
            throws XPathException

Export the global context item declaration to an SEF export file

Parameters:

out - the export destination

Throws:

XPathException - if things go wrong

setAbsentFocus

public void setAbsentFocus(boolean absent)

Say whether the global context item for a query or stylesheet will be absent. This is relevant only for XSLT.

Parameters:

absent - true if there will be no context item (externally or internally supplied).

isAbsentFocus

public boolean isAbsentFocus()

Ask whether the global context item for a query or stylesheet will be absent. This is relevant only for XSLT.

Returns:

true if there will be no context item (externally or internally supplied).

setMayBeOmitted

public void setMayBeOmitted(boolean mayOmit)

Say whether it is OK for the application to supply no context item

Parameters:

mayOmit - true if it is OK for the application to supply to context item

isMayBeOmitted

public boolean isMayBeOmitted()

Ask whether it is OK for the application to supply no context item

Returns:

true if it is OK for the application to supply to context item

setExternal

public void setExternal(boolean external)

Say whether (in XQuery) the global context item is declared as external

Parameters:

external - true if the global context item is declared as external

isExternal

public boolean isExternal()

Ask whether (in XQuery) the global context item is declared as external

Returns:

true if the global context item is declared as external