Class ApplyTemplates

All Implemented Interfaces:
Serializable, SourceLocator, LocationProvider, SaxonLocator, EvaluableItem, SequenceIterable, TailCallReturner, InstructionInfo, Locator

public class ApplyTemplates extends Instruction
An instruction representing an xsl:apply-templates element in the stylesheet
See Also:
  • Constructor Details

    • ApplyTemplates

      public ApplyTemplates(Expression select, boolean useCurrentMode, boolean useTailRecursion, Mode mode, boolean backwardsCompatible, boolean implicitSelect)
      Construct an apply-templates instructino
      Parameters:
      select - the select expression
      useCurrentMode - true if mode="#current" was specified
      useTailRecursion - true if this instruction is the last in its template
      mode - the mode specified on apply-templates
      backwardsCompatible - true if XSLT backwards compatibility is enabled
      implicitSelect - true if the select attribute was defaulted
  • Method Details

    • setActualParameters

      public void setActualParameters(WithParam[] actualParams, WithParam[] tunnelParams)
      Set the actual parameters on the call
      Parameters:
      actualParams - represents the contained xsl:with-param elements having tunnel="no" (the default)
      tunnelParams - represents the contained xsl:with-param elements having tunnel="yes"
    • getInstructionNameCode

      public int getInstructionNameCode()
      Get the name of this instruction for diagnostic and tracing purposes
      Overrides:
      getInstructionNameCode in class Instruction
      Returns:
      a code identifying the instruction: typically but not always the fingerprint of a name in the XSLT namespace
    • simplify

      public Expression simplify(ExpressionVisitor visitor) throws XPathException
      Simplify an expression. This performs any static optimization (by rewriting the expression as a different expression).
      Specified by:
      simplify in class Instruction
      Parameters:
      visitor - the expression visitor
      Returns:
      the simplified expression
      Throws:
      XPathException - if an error is discovered during expression rewriting
    • typeCheck

      public Expression typeCheck(ExpressionVisitor visitor, ItemType contextItemType) throws XPathException
      Description copied from class: Expression
      Perform type checking of an expression and its subexpressions. This is the second phase of static optimization.

      This checks statically that the operands of the expression have the correct type; if necessary it generates code to do run-time type checking or type conversion. A static type error is reported only if execution cannot possibly succeed, that is, if a run-time type error is inevitable. The call may return a modified form of the expression.

      This method is called after all references to functions and variables have been resolved to the declaration of the function or variable. However, the types of such functions and variables may not be accurately known if they have not been explicitly declared.

      If the implementation returns a value other than "this", then it is required to ensure that the parent pointer and location information in the returned expression have been set up correctly. It should not rely on the caller to do this, although for historical reasons many callers do so.

      Overrides:
      typeCheck in class Expression
      Parameters:
      visitor - an expression visitor
      contextItemType - the static type of "." at the point where this expression is invoked. The parameter is set to null if it is known statically that the context item will be undefined. If the type of the context item is not known statically, the argument is set to Type.ITEM_TYPE
      Returns:
      the original expression, rewritten to perform necessary run-time type checks, and to perform other type-related optimizations
      Throws:
      XPathException - if an error is discovered during this phase (typically a type error)
    • optimize

      public Expression optimize(ExpressionVisitor visitor, ItemType contextItemType) throws XPathException
      Description copied from class: Expression
      Perform optimisation of an expression and its subexpressions. This is the third and final phase of static optimization.

      This method is called after all references to functions and variables have been resolved to the declaration of the function or variable, and after all type checking has been done.

      Overrides:
      optimize in class Expression
      Parameters:
      visitor - an expression visitor
      contextItemType - the static type of "." at the point where this expression is invoked. The parameter is set to null if it is known statically that the context item will be undefined. If the type of the context item is not known statically, the argument is set to Type.ITEM_TYPE
      Returns:
      the original expression, rewritten if appropriate to optimize execution
      Throws:
      XPathException - if an error is discovered during this phase (typically a type error)
    • copy

      public Expression copy()
      Copy an expression. This makes a deep copy.
      Specified by:
      copy in class Expression
      Returns:
      the copy of the original expression
    • createsNewNodes

      public final boolean createsNewNodes()
      Determine whether this instruction creates new nodes. This implementation returns true (which is almost invariably the case, so it's not worth doing any further analysis to find out more precisely).
      Overrides:
      createsNewNodes in class Instruction
      Returns:
      true if the instruction creates new nodes (or if it can't be proved that it doesn't)
    • process

      public void process(XPathContext context) throws XPathException
      Description copied from class: Instruction
      Process the instruction, without returning any tail calls
      Overrides:
      process in class Instruction
      Parameters:
      context - The dynamic context, giving access to the current node, the current variables, etc.
      Throws:
      XPathException
    • processLeavingTail

      public TailCall processLeavingTail(XPathContext context) throws XPathException
      Description copied from class: Instruction
      ProcessLeavingTail: called to do the real work of this instruction. This method must be implemented in each subclass. The results of the instruction are written to the current Receiver, which can be obtained via the Controller.
      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
    • applyTemplates

      public static TailCall applyTemplates(SequenceIterator iterator, Mode mode, ParameterSet parameters, ParameterSet tunnelParameters, XPathContextMajor context, boolean backwardsCompatible, int locationId) throws XPathException
      Process selected nodes using the handlers registered for a particular mode.
      Parameters:
      iterator - an Iterator over the nodes to be processed, in the correct (sorted) order
      mode - Identifies the processing mode. It should match the mode defined when the element handler was registered using setHandler with a mode parameter. Set this parameter to null to invoke the default mode.
      parameters - A ParameterSet containing the parameters to the handler/template being invoked. Specify null if there are no parameters.
      tunnelParameters - A ParameterSet containing the parameters to the handler/template being invoked. Specify null if there are no parameters.
      context - A newly-created context object (this must be freshly created by the caller, as it will be modified by this method)
      backwardsCompatible - true if running in backwards compatibility mode
      locationId - location of this apply-templates instruction in the stylesheet
      Returns:
      a TailCall returned by the last template to be invoked, or null, indicating that there are no outstanding tail calls.
      Throws:
      XPathException - if any dynamic error occurs
    • defaultAction

      public static void defaultAction(NodeInfo node, ParameterSet parameters, ParameterSet tunnelParams, XPathContext context, boolean backwardsCompatible, int locationId) throws XPathException
      Perform the built-in template action for a given node.
      Parameters:
      node - the node to be processed
      parameters - the parameters supplied to apply-templates
      tunnelParams - the tunnel parameters to be passed through
      context - the dynamic evaluation context
      backwardsCompatible - true if in 1.0 mode (currently makes no difference)
      locationId - location of the instruction (apply-templates, apply-imports etc) that caused the built-in template to be invoked
      Throws:
      XPathException - if any dynamic error occurs
    • iterateSubExpressions

      public 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 Expression
      Returns:
      an iterator containing the sub-expressions of this expression
    • hasLoopingSubexpression

      public boolean hasLoopingSubexpression(Expression child)
      Given an expression that is an immediate child of this expression, test whether the evaluation of the parent expression causes the child expression to be evaluated repeatedly
      Overrides:
      hasLoopingSubexpression in class Expression
      Parameters:
      child - the immediate subexpression
      Returns:
      true if the child expression is evaluated repeatedly
    • replaceSubExpression

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

      public Expression getSelectExpression()
      Get the select expression
      Returns:
      the select expression
    • promoteInst

      protected void promoteInst(PromotionOffer offer) throws XPathException
      Handle promotion offers, that is, non-local tree rewrites.
      Overrides:
      promoteInst in class Instruction
      Parameters:
      offer - The type of rewrite being offered
      Throws:
      XPathException
    • explain

      public void explain(ExpressionPresenter out)
      Diagnostic print of expression structure. The abstract expression tree is written to the supplied output destination.
      Specified by:
      explain in class Expression
      Parameters:
      out - output destination