net.sf.saxon.functions

Class Id

public class Id extends SystemFunction

The XPath id() or element-with-id() function XPath 2.0 version: accepts any sequence as the first parameter; each item in the sequence is taken as an IDREFS value, that is, a space-separated list of ID values. Also accepts an optional second argument to identify the target document, this defaults to the context node.
Field Summary
static intELEMENT_WITH_ID
static intID
Method Summary
PathMap.PathMapNodeSetaddToPathMap(PathMap pathMap, PathMap.PathMapNodeSet pathMapNodeSet)
Add a representation of a doc() call or similar function to a PathMap.
voidcheckArguments(ExpressionVisitor visitor)
Static analysis: prevent sorting of the argument
intcomputeSpecialProperties()
Get the static properties of this expression (other than its type).
static SequenceIteratorgetIdMultiple(DocumentInfo doc, SequenceIterator idrefs, int operation)
Get an iterator over the nodes that have an id equal to one of the values is a set of whitespace separated strings
static SequenceIteratorgetIdMultiple(DocumentInfo doc, SequenceIterator idrefs)
Get an iterator over the nodes that have an id equal to one of the values is a set of whitespace separated strings.
static SequenceIteratorgetIdSingle(DocumentInfo doc, String idrefs, int operation)
Get an iterator over the nodes that have an id equal to one of the values is a whitespace separated string
static SequenceIteratorgetIdSingle(DocumentInfo doc, String idrefs)
2-argument version of getIdSingle, retained to support Java code compiled using Saxon 9.1.
SequenceIteratoriterate(XPathContext context)
Evaluate the function to return an iteration of selected nodes.
ExpressionpreEvaluate(ExpressionVisitor visitor)
preEvaluate: this method suppresses compile-time evaluation by doing nothing
Expressionsimplify(ExpressionVisitor visitor)
Simplify: add a second implicit argument, the context document
ExpressiontypeCheck(ExpressionVisitor visitor, ItemType contextItemType)
Type-check the expression.

Field Detail

ELEMENT_WITH_ID

public static final int ELEMENT_WITH_ID

ID

public static final int ID

Method Detail

addToPathMap

public PathMap.PathMapNodeSet addToPathMap(PathMap pathMap, PathMap.PathMapNodeSet pathMapNodeSet)
Add a representation of a doc() call or similar function to a PathMap. This is a convenience method called by the addToPathMap() methods for doc(), document(), collection() and similar functions. These all create a new root expression in the path map.

Parameters: pathMap the PathMap to which the expression should be added pathMapNodeSet

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

checkArguments

public void checkArguments(ExpressionVisitor visitor)
Static analysis: prevent sorting of the argument

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.

getIdMultiple

public static SequenceIterator getIdMultiple(DocumentInfo doc, SequenceIterator idrefs, int operation)
Get an iterator over the nodes that have an id equal to one of the values is a set of whitespace separated strings

Parameters: doc The document to be searched idrefs an iterator over a set of strings each of which is a string containing zero or more whitespace-separated ID values to be found in the document

Returns: an iterator over the nodes whose ID is one of the specified values

Throws: XPathException

getIdMultiple

public static SequenceIterator getIdMultiple(DocumentInfo doc, SequenceIterator idrefs)
Get an iterator over the nodes that have an id equal to one of the values is a set of whitespace separated strings. 2-argument version retained to support Java code compiled under Saxon 9.1

Parameters: doc The document to be searched idrefs an iterator over a set of strings each of which is a string containing zero or more whitespace-separated ID values to be found in the document

Returns: an iterator over the nodes whose ID is one of the specified values

Throws: XPathException

getIdSingle

public static SequenceIterator getIdSingle(DocumentInfo doc, String idrefs, int operation)
Get an iterator over the nodes that have an id equal to one of the values is a whitespace separated string

Parameters: doc The document to be searched idrefs a string containing zero or more whitespace-separated ID values to be found in the document operation either ID or ELEMENT_WITH_ID

Returns: an iterator over the nodes whose ID is one of the specified values

Throws: XPathException

getIdSingle

public static SequenceIterator getIdSingle(DocumentInfo doc, String idrefs)
2-argument version of getIdSingle, retained to support Java code compiled using Saxon 9.1. Operation defaults to ID.

Parameters: doc The document to be searched idrefs a string containing zero or more whitespace-separated ID values to be found in the document

Returns: an iterator over the nodes whose ID is one of the specified values

Throws: XPathException

iterate

public SequenceIterator iterate(XPathContext context)
Evaluate the function to return an iteration of selected nodes.

preEvaluate

public Expression preEvaluate(ExpressionVisitor visitor)
preEvaluate: this method suppresses compile-time evaluation by doing nothing

Parameters: visitor an expression visitor

simplify

public Expression simplify(ExpressionVisitor visitor)
Simplify: add a second implicit argument, the context document

Parameters: visitor an expression visitor

typeCheck

public Expression typeCheck(ExpressionVisitor visitor, ItemType contextItemType)
Type-check the expression. This also calls preEvaluate() to evaluate the function if all the arguments are constant; functions that do not require this behavior can override the preEvaluate method.