net.sf.saxon.functions
Class DocumentFn

java.lang.Object
  net.sf.saxon.expr.Expression
      net.sf.saxon.expr.FunctionCall
          net.sf.saxon.functions.SystemFunction
              net.sf.saxon.functions.DocumentFn

All Implemented Interfaces:

Serializable, SourceLocator, LocationProvider, SaxonLocator, CallableExpression, InstructionInfo, Locator

public class DocumentFn
extends SystemFunction
implements CallableExpression

Implements the XSLT document() function

See Also:

Serialized Form

Field Summary

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

operation

Fields inherited from class net.sf.saxon.expr.FunctionCall

argument

Fields inherited from class net.sf.saxon.expr.Expression

EFFECTIVE_BOOLEAN_VALUE, EVALUATE_METHOD, EVENT_FEED_METHOD, ITEM_FEED_METHOD, ITERATE_METHOD, locationId, MAX_SEQUENCE_LENGTH, MAX_STRING_LENGTH, PROCESS_METHOD, PUSH_SELECTION, staticProperties, UNBOUNDED_LOWER, UNBOUNDED_UPPER, WATCH_METHOD

Constructor Summary

DocumentFn()

Method Summary

PathMap.PathMapNodeSet	addToPathMap(PathMap pathMap, PathMap.PathMapNodeSet pathMapNodeSet) Add a representation of this expression to a PathMap.
SequenceIterator	call(SequenceIterator[] arguments, XPathContext context) Evaluate the expression
void	checkArguments(ExpressionVisitor visitor) Method called during static type checking
int	computeCardinality() Determine the static cardinality
static DocumentURI	computeDocumentKey(String href, String baseURI, URIResolver resolver) Compute a document key (an absolute URI that can be used to see if a document is already loaded)
protected static DocumentURI	computeDocumentKey(String href, String baseURI, XPathContext c) Compute a document key
int	computeSpecialProperties() Get the static properties of this expression (other than its type).
Expression	copy() Copy an expression.
boolean	equals(Object o) Determine whether two expressions are equivalent
String	getStaticBaseURI() Get the base URI from the static context
SequenceIterator	iterate(XPathContext context) iterate() handles evaluation of the function: it returns a sequence of Document nodes
static NodeInfo	makeDoc(String href, String baseURI, XPathContext c, SourceLocator locator) Supporting routine to load one external document given a URI (href) and a baseURI.
Expression	preEvaluate(ExpressionVisitor visitor) preEvaluate: the document() function can be evaluated at compile time if (a) the argument is a string literal, and (b) the option FeatureKeys.PRE_EVALUATE_DOC_FUNCTION is set.
static NodeInfo	preLoadDoc(String href, String baseURI, Configuration config, SourceLocator locator) Supporting routine to load one external document given a URI (href) and a baseURI.
static Source	resolveURI(String href, String baseURI, String documentKey, Controller controller) Call the URIResolver to resolve a URI
static void	sendDoc(String href, String baseURL, XPathContext c, SourceLocator locator, Receiver out) Supporting routine to push one external document given a URI (href) and a baseURI to a given Receiver.
void	sendDocuments(XPathContext context, Receiver out) Copy the documents identified by this expression to a given Receiver.

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

addContextDocumentArgument, addDocToPathMap, getDetails, getErrorCodeForTypeErrors, getImplementationMethod, getItemType, getOperation, getRequiredType, makeSystemFunction, optimize, setDetails, useContextItemAsDefault

Methods inherited from class net.sf.saxon.expr.FunctionCall

addExternalFunctionCallToPathMap, checkArgumentCount, explain, getArguments, getDisplayName, getExpressionName, getFunctionName, getNumberOfArguments, hashCode, iterateSubExpressions, promote, replaceSubExpression, setArguments, setFunctionName, simplify, simplifyArguments, toString, typeCheck

Methods inherited from class net.sf.saxon.expr.Expression

adoptChildExpression, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeStaticProperties, doPromotion, dynamicError, effectiveBooleanValue, evaluateAsString, evaluateItem, evaluatePendingUpdates, explain, getCardinality, getColumnNumber, getColumnNumber, getConstructType, getContainer, getDependencies, getEvaluationMethod, getExecutable, getHostLanguage, getIntegerBounds, getIntrinsicDependencies, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getObjectName, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, getSystemId, hasLoopingSubexpression, hasVariableBinding, implementsStaticTypeCheck, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, iterateEvents, iterateSameFocusSubExpressions, markTailFunctionCalls, process, resetLocalStaticProperties, setContainer, setEvaluationMethod, setFiltered, setFlattened, setLocationId, staticTypeCheck, suppressValidation, typeError

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface net.sf.saxon.expr.CallableExpression

getArguments

Constructor Detail

DocumentFn

public DocumentFn()

Method Detail

checkArguments

public void checkArguments(ExpressionVisitor visitor)
                    throws XPathException

Method called during static type checking

Overrides:

checkArguments in class SystemFunction

Parameters:

visitor - the expression visitor

Throws:

XPathException - if the arguments are incorrect

computeCardinality

public int computeCardinality()

Determine the static cardinality

Overrides:

computeCardinality in class SystemFunction

Returns:

the computed cardinality, as one of the values StaticProperty.ALLOWS_ZERO_OR_ONE, StaticProperty.EXACTLY_ONE, StaticProperty.ALLOWS_ONE_OR_MORE, StaticProperty.ALLOWS_ZERO_OR_MORE

getStaticBaseURI

public String getStaticBaseURI()

Get the base URI from the static context

Returns:

the base URI

computeSpecialProperties

public int computeSpecialProperties()

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:

computeSpecialProperties in class SystemFunction

Returns:

the special properties, as a bit-significant integer

preEvaluate

public Expression preEvaluate(ExpressionVisitor visitor)

preEvaluate: the document() function can be evaluated at compile time if (a) the argument is a string literal, and (b) the option FeatureKeys.PRE_EVALUATE_DOC_FUNCTION is set.

Overrides:

preEvaluate in class FunctionCall

Parameters:

visitor - an expression visitor

Returns:

the result of the early evaluation, or the original expression, or potentially a simplified expression

addToPathMap

public PathMap.PathMapNodeSet addToPathMap(PathMap pathMap,
                                           PathMap.PathMapNodeSet pathMapNodeSet)

Add a representation of this expression to a PathMap. The PathMap captures a map of the nodes visited by an expression in a source tree.

Overrides:

addToPathMap in class Expression

Parameters:

pathMap - the PathMap to which the expression should be added

pathMapNodeSet - the set of nodes in the path map that are affected

Returns:

the pathMapNode representing the focus established by this expression, in the case where this expression is the first operand of a path expression or filter expression

copy

public Expression copy()

Copy an expression. This makes a deep copy.

Overrides:

copy in class SystemFunction

Returns:

the copy of the original expression

equals

public boolean equals(Object o)

Determine whether two expressions are equivalent

Overrides:

equals in class SystemFunction

iterate

public SequenceIterator iterate(XPathContext context)
                         throws XPathException

iterate() handles evaluation of the function: it returns a sequence of Document nodes

Overrides:

iterate in class Expression

Parameters:

context - supplies the context for evaluation

Returns:

a SequenceIterator that can be used to iterate over the result of the expression

Throws:

XPathException - if any dynamic error occurs evaluating the expression

call

public SequenceIterator call(SequenceIterator[] arguments,
                             XPathContext context)
                      throws XPathException

Evaluate the expression

Specified by:

call in interface CallableExpression

Parameters:

arguments - the values of the arguments, supplied as SequenceIterators

context - the dynamic evaluation context

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

makeDoc

public static NodeInfo makeDoc(String href,
                               String baseURI,
                               XPathContext c,
                               SourceLocator locator)
                        throws XPathException

Supporting routine to load one external document given a URI (href) and a baseURI. This is used in the normal case when a document is loaded at run-time (that is, when a Controller is available)

Parameters:

href - the relative URI

baseURI - the base URI

c - the dynamic XPath context

locator - used to identify the location of the instruction in event of error

Returns:

the root of the constructed document, or the selected element within the document if a fragment identifier was supplied

Throws:

XPathException

resolveURI

public static Source resolveURI(String href,
                                String baseURI,
                                String documentKey,
                                Controller controller)
                         throws XPathException

Call the URIResolver to resolve a URI

Parameters:

href - the supplied relative URI, stripped of any fragment identifier

baseURI - the base URI

documentKey - the absolute URI if already available, or null otherwise

controller - the Saxon controller

Returns:

a Source representing the document to be read

Throws:

XPathException

computeDocumentKey

protected static DocumentURI computeDocumentKey(String href,
                                                String baseURI,
                                                XPathContext c)
                                         throws XPathException

Compute a document key

Throws:

XPathException

computeDocumentKey

public static DocumentURI computeDocumentKey(String href,
                                             String baseURI,
                                             URIResolver resolver)
                                      throws XPathException

Compute a document key (an absolute URI that can be used to see if a document is already loaded)

Parameters:

href - the relative URI

baseURI - the base URI

resolver - the URIResolver

Throws:

XPathException

preLoadDoc

public static NodeInfo preLoadDoc(String href,
                                  String baseURI,
                                  Configuration config,
                                  SourceLocator locator)
                           throws XPathException

Supporting routine to load one external document given a URI (href) and a baseURI. This is used when the document is pre-loaded at compile time.

Parameters:

href - the relative URI. This must not contain a fragment identifier

baseURI - the base URI

config - the Saxon configuration

locator - used to identify the location of the instruction in event of error. May be null.

Returns:

the root of the constructed document, or the selected element within the document if a fragment identifier was supplied

Throws:

XPathException

sendDocuments

public void sendDocuments(XPathContext context,
                          Receiver out)
                   throws XPathException

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

Parameters:

context - the XPath dynamic context

out - the destination to which the documents will be sent

Throws:

XPathException

sendDoc

public static void sendDoc(String href,
                           String baseURL,
                           XPathContext c,
                           SourceLocator locator,
                           Receiver out)
                    throws XPathException

Supporting routine to push one external document given a URI (href) and a baseURI to a given Receiver. This method cannot handle fragment identifiers

Parameters:

href - the relative URI

baseURL - the base URI

c - the XPath dynamic context

locator - used to identify the lcoation of the instruction in case of error

out - the destination where the document is to be sent

Throws:

XPathException