com.icl.saxon.expr

Class AttributeReference


(package private) class AttributeReference
extends SingletonExpression

An expression that represents a reference to a named attribute

Field Summary

Fields inherited from class com.icl.saxon.expr.Expression

staticContext

Constructor Summary

AttributeReference(int fingerprint)
Constructor

Method Summary

void
bindParentNode(NodeInfo node)
Bind the reference to a particular node
void
display(int level)
Diagnostic print of expression structure
boolean
evaluateAsBoolean(Context context)
Evaluate as a boolean.
String
evaluateAsString(Context context)
Evaluate as a string.
int
getDependencies()
Determine which aspects of the context the expression depends on.
NodeInfo
getNode(Context context)
Return the relevant attribute node
Expression
reduce(int dependencies, Context context)
Perform a partial evaluation of the expression, by eliminating specified dependencies on the context.

Methods inherited from class com.icl.saxon.expr.SingletonExpression

enumerate, evaluateAsBoolean, evaluateAsNodeSet, evaluateAsString, getNode, isContextDocumentNodeSet, selectFirst

Methods inherited from class com.icl.saxon.expr.NodeSetExpression

enumerate, evaluate, evaluateAsBoolean, evaluateAsNodeSet, evaluateAsString, getDataType, outputStringValue, selectFirst

Methods inherited from class com.icl.saxon.expr.Expression

containsReferences, display, enumerate, evaluate, evaluateAsBoolean, evaluateAsNodeSet, evaluateAsNumber, evaluateAsString, getDataType, getDependencies, getStaticContext, indent, isContextDocumentNodeSet, make, outputStringValue, reduce, setStaticContext, simplify, usesCurrent

Constructor Details

AttributeReference

public AttributeReference(int fingerprint)
Constructor

Method Details

bindParentNode

public void bindParentNode(NodeInfo node)
Bind the reference to a particular node

display

public void display(int level)
Diagnostic print of expression structure
Overrides:
display in interface Expression

evaluateAsBoolean

public boolean evaluateAsBoolean(Context context)
            throws XPathException
Evaluate as a boolean. Returns true if there are any nodes selected by the NodeSetExpression
Overrides:
evaluateAsBoolean in interface SingletonExpression
Parameters:
context - The context in which the expression is to be evaluated
Returns:
true if there are any nodes selected by the NodeSetExpression

evaluateAsString

public String evaluateAsString(Context context)
            throws XPathException
Evaluate as a string. Returns the string value of the attribute if it exists
Overrides:
evaluateAsString in interface SingletonExpression
Parameters:
context - The context in which the expression is to be evaluated
Returns:
true if there are any nodes selected by the NodeSetExpression

getDependencies

public int getDependencies()
Determine which aspects of the context the expression depends on. The result is a bitwise-or'ed value composed from constants such as Context.VARIABLES and Context.CURRENT_NODE
Overrides:
getDependencies in interface Expression

getNode

public NodeInfo getNode(Context context)
            throws XPathException
Return the relevant attribute node
Overrides:
getNode in interface SingletonExpression
Parameters:
context - the evaluation context

reduce

public Expression reduce(int dependencies,
                         Context context)
            throws XPathException
Perform a partial evaluation of the expression, by eliminating specified dependencies on the context.
Overrides:
reduce in interface Expression
Parameters:
dependencies - The dependencies to be removed
context - The context to be used for the partial evaluation
Returns:
a new expression that does not have any of the specified dependencies