net.sf.saxon.expr
Class AttributeReference

java.lang.Object
  net.sf.saxon.expr.ComputedExpression
      net.sf.saxon.expr.SingleNodeExpression
          net.sf.saxon.expr.AttributeReference

All Implemented Interfaces:

Serializable, Expression

public class AttributeReference
extends SingleNodeExpression

An expression that represents a reference to a named attribute

See Also:

Serialized Form

Field Summary

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

lineNumber, NO_ARGUMENTS, staticProperties

Constructor Summary

AttributeReference(int fingerprint)
Constructor

Method Summary

int	computeSpecialProperties() getProperties(): return properties of this expression, for optimization
void	display(int level, NamePool pool) Diagnostic print of expression structure
boolean	effectiveBooleanValue(XPathContext context) Evaluate as a boolean.
boolean	equals(Object other) Is this expression the same as another expression?
String	evaluateAsString(XPathContext context) Evaluate as a string.
ItemType	getItemType() Determine the data type of the items returned by this expression
NameTest	getNameTest() Get the attribute name test
NodeInfo	getNode(XPathContext context) Return the relevant attribute node
int	hashCode() get HashCode for comparing two expressions

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

analyze, computeCardinality, evaluateItem, getIntrinsicDependencies, iterate

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

computeDependencies, computeStaticProperties, dynamicError, getCardinality, getDependencies, getLineNumber, getSpecialProperties, getSubExpressions, markTailFunctionCalls, promote, setLineNumber, simplify, typeError

Methods inherited from class java.lang.Object

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

Constructor Detail

AttributeReference

public AttributeReference(int fingerprint)

Constructor

Method Detail

getItemType

public ItemType getItemType()

Determine the data type of the items returned by this expression

Specified by:

getItemType in interface Expression

Overrides:

getItemType in class SingleNodeExpression

Returns:

the type attribute()

getNameTest

public NameTest getNameTest()

Get the attribute name test

computeSpecialProperties

public int computeSpecialProperties()

getProperties(): return properties of this expression, for optimization

Overrides:

computeSpecialProperties in class ComputedExpression

equals

public boolean equals(Object other)

Is this expression the same as another expression?

Overrides:

equals in class Object

hashCode

public int hashCode()

get HashCode for comparing two expressions

Overrides:

hashCode in class Object

getNode

public NodeInfo getNode(XPathContext context)
                 throws XPathException

Return the relevant attribute node

Specified by:

getNode in class SingleNodeExpression

Parameters:

context - the evaluation context

Throws:

XPathException

effectiveBooleanValue

public boolean effectiveBooleanValue(XPathContext context)
                              throws XPathException

Evaluate as a boolean. Returns true if there are any nodes selected by the Expression

Specified by:

effectiveBooleanValue in interface Expression

Overrides:

effectiveBooleanValue in class SingleNodeExpression

Parameters:

context - The context in which the expression is to be evaluated

Returns:

true if there are any nodes selected by the Expression

Throws:

XPathException - if any dynamic error occurs evaluating the expression

evaluateAsString

public String evaluateAsString(XPathContext context)
                        throws XPathException

Evaluate as a string. Returns the string value of the attribute if it exists

Specified by:

evaluateAsString in interface Expression

Overrides:

evaluateAsString in class ComputedExpression

Parameters:

context - The context in which the expression is to be evaluated

Returns:

the string value of the attribute if present, or "" otherwise

Throws:

XPathException - if any dynamic error occurs evaluating the expression

display

public void display(int level,
                    NamePool pool)

Diagnostic print of expression structure

Parameters:

level - indentation level for this expression