Class LocalParam

  • All Implemented Interfaces:
    java.io.Serializable, javax.xml.transform.SourceLocator, LocationProvider, SaxonLocator, Binding, EvaluableItem, SequenceIterable, TailCallReturner, InstructionInfo, org.xml.sax.Locator

    public final class LocalParam
    extends GeneralVariable
    The compiled form of an xsl:param element within a template in an XSLT stylesheet.

    The xsl:param element in XSLT has mandatory attribute name and optional attribute select. It can also be specified as required="yes" or required="no".

    This is used only for parameters to XSLT templates. For function calls, the caller of the function places supplied arguments onto the callee's stackframe and the callee does not need to do anything. Global parameters (XQuery external variables) are handled using GlobalParam.

    See Also:
    Serialized Form
    • Constructor Detail

      • LocalParam

        public LocalParam()
    • Method Detail

      • setParameterId

        public void setParameterId​(int id)
        Allocate a number which is essentially an alias for the parameter name, unique within a stylesheet
        Parameters:
        id - the parameter id
      • getParameterId

        public int getParameterId()
        Get the parameter id, which is essentially an alias for the parameter name, unique within a stylesheet
        Returns:
        the parameter id
      • setConversion

        public void setConversion​(Expression convertor)
        Define a conversion that is to be applied to the supplied parameter value.
        Parameters:
        convertor - The expression to be applied. This performs type checking, and the basic conversions implied by function calling rules, for example numeric promotion, atomization, and conversion of untyped atomic values to a required type. The conversion uses the actual parameter value as input, referencing it using a VariableReference.
      • getInstructionNameCode

        public int getInstructionNameCode()
        Get the name of this instruction for diagnostic and tracing purposes
        Overrides:
        getInstructionNameCode in class GeneralVariable
        Returns:
        the name of this instruction, as a name pool name code
      • iterateSubExpressions

        public java.util.Iterator iterateSubExpressions()
        Get all the XPath expressions associated with this instruction (in XSLT terms, the expression present on attributes of the instruction, as distinct from the child instructions in a sequence construction)
        Overrides:
        iterateSubExpressions in class GeneralVariable
        Returns:
        an iterator containing the sub-expressions of this expression
      • replaceSubExpression

        public boolean replaceSubExpression​(Expression original,
                                            Expression replacement)
        Replace one subexpression by a replacement subexpression
        Overrides:
        replaceSubExpression in class GeneralVariable
        Parameters:
        original - the original subexpression
        replacement - the replacement subexpression
        Returns:
        true if the original subexpression is found
      • processLeavingTail

        public TailCall processLeavingTail​(XPathContext context)
                                    throws XPathException
        Process the local parameter declaration
        Specified by:
        processLeavingTail in interface TailCallReturner
        Specified by:
        processLeavingTail in class Instruction
        Parameters:
        context - The dynamic context of the transformation, giving access to the current node, the current variables, etc.
        Returns:
        null if the instruction has completed execution; or a TailCall indicating a function call or template call that is delegated to the caller, to be made after the stack has been unwound so as to save stack space.
        Throws:
        XPathException
      • evaluateVariable

        public ValueRepresentation evaluateVariable​(XPathContext c)
        Evaluate the variable
        Parameters:
        c - the XPath dynamic evaluation context
        Returns:
        the result of evaluating the variable
      • explain

        public void explain​(ExpressionPresenter out)
        Diagnostic print of expression structure. The abstract expression tree is written to the supplied output destination.
        Overrides:
        explain in class GeneralVariable
        Parameters:
        out - the expression presenter used to display the structure