net.sf.saxon.functions
Class Document

java.lang.Object
  extended by net.sf.saxon.expr.Expression
      extended by net.sf.saxon.expr.FunctionCall
          extended by net.sf.saxon.functions.SystemFunction
              extended by net.sf.saxon.functions.Document
All Implemented Interfaces:
Serializable, SourceLocator, LocationProvider, SaxonLocator, EvaluableItem, SequenceIterable, InstructionInfo, Locator

public class Document
extends SystemFunction

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
EVALUATE_METHOD, ITERATE_METHOD, locationId, PROCESS_METHOD, staticProperties
 
Constructor Summary
Document()
           
 
Method Summary
 PathMap.PathMapNodeSet addToPathMap(PathMap pathMap, PathMap.PathMapNodeSet pathMapNodeSet)
          Add a representation of this expression to a PathMap.
 void checkArguments(ExpressionVisitor visitor)
          Method called during static type checking
 int computeCardinality()
          Determine the static cardinality
protected static String 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.
 String getStaticBaseURI()
          Get the base URI from the static context
 boolean isReadOnce()
          Ask whether this document has been marked as being read once only.
 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.
 void setReadOnce(boolean once)
          Indicate that the document(s) will be read once only (or that they should be treated as if they are read once only.
 
Methods inherited from class net.sf.saxon.functions.SystemFunction
addContextDocumentArgument, addDocToPathMap, getDetails, getErrorCodeForTypeErrors, getItemType, getRequiredType, makeSystemFunction, optimize, setDetails, useContextItemAsDefault
 
Methods inherited from class net.sf.saxon.expr.FunctionCall
addExternalFunctionCallToPathMap, checkArgumentCount, equals, explain, getArguments, getDisplayName, 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, getExecutable, getHostLanguage, getImplementationMethod, getIntrinsicDependencies, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getObjectName, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, getSystemId, hasLoopingSubexpression, implementsStaticTypeCheck, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, iterateEvents, iterateSameFocusSubExpressions, markTailFunctionCalls, process, resetLocalStaticProperties, setContainer, setFiltered, setFlattened, setLocationId, staticTypeCheck, suppressValidation, typeError
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Constructor Detail

Document

public Document()
Method Detail

setReadOnce

public void setReadOnce(boolean once)
Indicate that the document(s) will be read once only (or that they should be treated as if they are 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

checkArguments

public void checkArguments(ExpressionVisitor visitor)
                    throws XPathException
Description copied from class: SystemFunction
Method called during static type checking

Overrides:
checkArguments in class SystemFunction
Parameters:
visitor - the expression visitor
Throws:
XPathException

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

iterate

public SequenceIterator iterate(XPathContext context)
                         throws XPathException
iterate() handles evaluation of the function: it returns a sequence of Document nodes

Specified by:
iterate in interface SequenceIterable
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

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 String computeDocumentKey(String href,
                                           String baseURI,
                                           XPathContext c)
                                    throws XPathException
Compute a document key

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


Copyright (c) Saxonica Limited. All rights reserved.