com.icl.saxon.expr
Class AttributeValueTemplate

java.lang.Object
  com.icl.saxon.expr.Expression
      com.icl.saxon.expr.AttributeValueTemplate

public final class AttributeValueTemplate

extends Expression

This class represents an attribute value template. Although it is not technically an expression in the sense of XSL syntax, we model it as an expression for inheritance purposes.

Field Summary

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

staticContext

Method Summary

void	display(int level) Diagnostic print of expression structure
Value	evaluate(Context context) Evaluate an AVT.
java.lang.String	evaluateAsString(Context context) Evaluate an expression as a String.
int	getDataType() Determine the data type of the expression, if possible
int	getDependencies() Determine which aspects of the context the expression depends on.
static Expression	make(java.lang.String avt, StaticContext env) Static factory method to create an AVT from an XSL string representation
Expression	reduce(int dependencies, Context context) Perform a partial evaluation of the expression, by eliminating specified dependencies on the context.
Expression	simplify() Simplify an expression.

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

containsReferences, enumerate, evaluateAsBoolean, evaluateAsNodeSet, evaluateAsNumber, getStaticContext, indent, isContextDocumentNodeSet, outputStringValue, setStaticContext, usesCurrent

Methods inherited from class java.lang.Object

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

Method Detail

make

public static Expression make(java.lang.String avt,
                              StaticContext env)
                       throws XPathException

Static factory method to create an AVT from an XSL string representation

Throws:

XPathException

simplify

public Expression simplify()
                    throws XPathException

Simplify an expression.

Overrides:

simplify in class Expression

Returns:

the simplified expression

Throws:

XPathException

evaluate

public Value evaluate(Context context)
               throws XPathException

Evaluate an AVT.

Specified by:

evaluate in class Expression

Parameters:

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

Returns:

the value of the AVT, evaluated in the current context

Throws:

XPathException

getDataType

public int getDataType()

Determine the data type of the expression, if possible

Specified by:

getDataType in class Expression

Returns:

Value.STRING

evaluateAsString

public java.lang.String evaluateAsString(Context context)
                                  throws XPathException

Evaluate an expression as a String.

Overrides:

evaluateAsString in class Expression

Parameters:

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

Returns:

the value of the expression, evaluated in the current context

Throws:

XPathException

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

Specified by:

getDependencies in class Expression

reduce

public Expression reduce(int dependencies,
                         Context context)
                  throws XPathException

Perform a partial evaluation of the expression, by eliminating specified dependencies on the context.

Specified by:

reduce in class 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

Throws:

XPathException

display

public void display(int level)

Diagnostic print of expression structure

Specified by:

display in class Expression