net.sf.saxon.functions

Class Doc

java.lang.Object

net.sf.saxon.om.AbstractItem

net.sf.saxon.functions.AbstractFunction

net.sf.saxon.functions.SystemFunction

net.sf.saxon.functions.Doc

All Implemented Interfaces:

PullEvent, Callable, Function, GroundedValue, Item, Sequence

public class Doc
extends SystemFunction
implements Callable

Implement the fn:doc() function - a simplified form of the Document function

Constructor Summary

Constructors

Constructor and Description
Doc()

Method Summary

Methods

Modifier and Type	Method and Description
ZeroOrOne<NodeInfo>	call(XPathContext context, Sequence[] arguments) Evaluate the expression
int	getCardinality(Expression[] arguments) Get the cardinality, given knowledge of the actual arguments
ParseOptions	getParseOptions() Get the parsing options set via setParseOptions()
int	getSpecialProperties(Expression[] arguments) Get the static properties of this expression (other than its type).
boolean	isReadOnce() Ask whether this document has been marked as being read once only.
void	sendDocument(XPathContext context, Expression[] args, Receiver out) Copy the document identified by this expression to a given Receiver.
void	setParseOptions(ParseOptions parseOptions) Set options to be used for the parsing operation.
void	setReadOnce(boolean once) Indicate that the document will be read once only (or that it should be treated as if it is read once only.

Methods inherited from class net.sf.saxon.functions.SystemFunction

equals, export, exportAttributes, getArity, getContextNode, getDescription, getDetails, getErrorCodeForTypeErrors, getExpressionCompiler, getFunctionItemType, getFunctionName, getIntegerBounds, getOperandRoles, getRequiredType, getResultItemType, getResultItemType, getRetainedStaticContext, getStaticBaseUriString, getStreamingAdjunct, importAttributes, makeCall, makeFunction, makeFunctionCall, makeOptimizedFunctionCall, resultIfEmpty, setArity, setDetails, setRetainedStaticContext, supplyTypeInformation, typeCheckCaller

Methods inherited from class net.sf.saxon.functions.AbstractFunction

atomize, deepEquals, effectiveBooleanValue, getStringValue, getStringValueCS, isArray, isMap, optimize, simplify, typeCheck

Methods inherited from class net.sf.saxon.om.AbstractItem

getLength, head, itemAt, iterate, reduce, subsequence

Methods inherited from class java.lang.Object

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

Methods inherited from interface net.sf.saxon.om.Function

iterate

Methods inherited from interface net.sf.saxon.om.Item

head

Methods inherited from interface net.sf.saxon.om.GroundedValue

getLength, head, itemAt, reduce, subsequence

Constructor Detail

Doc

public Doc()

Method Detail

setReadOnce

public void setReadOnce(boolean once)

Indicate that the document will be read once only (or that it should be treated as if it is read once only. This means (a) the document will not be held in memory after all references to it go out of scope, and (b) if the query or transformation tries to read it again, it will get a new copy, with different node identities, and potentially with different content. It also means that the document is eligible for document projection.

Parameters:

once - true if this document is to be treated as being read once only

isReadOnce

public boolean isReadOnce()

Ask whether this document has been marked as being read once only.

Returns:

true if the document has been marked as being read once only

getParseOptions

public ParseOptions getParseOptions()

Get the parsing options set via setParseOptions()

Returns:

the parsing options

setParseOptions

public void setParseOptions(ParseOptions parseOptions)

Set options to be used for the parsing operation. Defaults to the parsing options set in the Configuration

Parameters:

parseOptions - the parsing options to be used. Currently only affects the behaviour of the sendDocument() method (used in streamed merging)

getCardinality

public int getCardinality(Expression[] arguments)

Description copied from class: SystemFunction

Get the cardinality, given knowledge of the actual arguments

Overrides:

getCardinality in class SystemFunction

Parameters:

arguments - the actual arguments supplied

Returns:

the most precise available cardinality that the function will return

call

public ZeroOrOne<NodeInfo> call(XPathContext context,
                       Sequence[] arguments)
                         throws XPathException

Evaluate the expression

Specified by:

call in interface Callable

Specified by:

call in interface Function

Parameters:

context - the dynamic evaluation context

arguments - the values of the arguments, supplied as SequenceIterators

Returns:

the result of the evaluation, in the form of a SequenceIterator

Throws:

XPathException - if a dynamic error occurs during the evaluation of the expression

getSpecialProperties

public int getSpecialProperties(Expression[] arguments)

Get the static properties of this expression (other than its type). The result is bit-signficant. These properties are used for optimizations. In general, if property bit is set, it is true, but if it is unset, the value is unknown.

Overrides:

getSpecialProperties in class SystemFunction

Parameters:

arguments -

sendDocument

public void sendDocument(XPathContext context,
                Expression[] args,
                Receiver out)
                  throws XPathException

Copy the document identified by this expression to a given Receiver. This method is used only when it is known that the document is being copied, because there is then no problem about node identity.

Parameters:

context - the XPath dynamic context

args - the arguments to the doc function

out - the destination to which the document will be sent

Throws:

XPathException - if a failure occurs