Class CallTemplate

All Implemented Interfaces:
Serializable, SourceLocator, Container, Expression, TailCallReturner, InstructionInfoProvider

public class CallTemplate extends Instruction
Instruction representing an xsl:call-template element in the stylesheet.
See Also:
  • Constructor Details

    • CallTemplate

      public CallTemplate(Template template, boolean useTailRecursion, Expression calledTemplateExpression, NamespaceResolver nsContext)
      Construct a CallTemplate instruction.
      Parameters:
      template - the Template object identifying the template to be called, in the normal case where this is known statically
      useTailRecursion -
      calledTemplateExpression - expression to calculate the name of the template to be called at run-time, this supports the saxon:allow-avt option
      nsContext - the static namespace context of the instruction, needed only in the case where the name of the called template is to be calculated dynamically
  • Method Details

    • setActualParameters

      public void setActualParameters(WithParam[] actualParams, WithParam[] tunnelParams)
      Set the actual parameters on the call
    • getInstructionNameCode

      public int getInstructionNameCode()
      Return the name of this instruction.
      Overrides:
      getInstructionNameCode in class Instruction
    • getInstructionInfo

      public InstructionInfo getInstructionInfo()
      Set additional trace properties appropriate to the kind of instruction. This implementation adds the template property, which identities the template to be called
      Specified by:
      getInstructionInfo in interface InstructionInfoProvider
      Overrides:
      getInstructionInfo in class Instruction
    • simplify

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

      public Expression typeCheck(StaticContext env, ItemType contextItemType) throws XPathException
      Description copied from interface: 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.

      Parameters:
      env - the static context of the expression
      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
    • optimize

      public Expression optimize(Optimizer opt, StaticContext env, ItemType contextItemType) throws XPathException
      Description copied from interface: 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.

      Parameters:
      opt - the optimizer in use. This provides access to supporting functions; it also allows different optimization strategies to be used in different circumstances.
      env - the static context of the expression
      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
    • getIntrinsicDependencies

      public int getIntrinsicDependencies()
      Description copied from class: ComputedExpression
      Determine the intrinsic dependencies of an expression, that is, those which are not derived from the dependencies of its subexpressions. For example, position() has an intrinsic dependency on the context position, while (position()+1) does not. The default implementation of the method returns 0, indicating "no dependencies".
      Overrides:
      getIntrinsicDependencies in class ComputedExpression
      Returns:
      a set of bit-significant flags identifying the "intrinsic" dependencies. The flags are documented in class net.sf.saxon.value.StaticProperty
    • createsNewNodes

      public final boolean createsNewNodes()
      Determine whether this instruction creates new nodes. This implementation currently returns true unconditionally.
      Overrides:
      createsNewNodes in class Instruction
    • 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)
      Specified by:
      iterateSubExpressions in interface Expression
      Overrides:
      iterateSubExpressions in class ComputedExpression
      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
      Specified by:
      replaceSubExpression in interface Container
      Overrides:
      replaceSubExpression in class ComputedExpression
      Parameters:
      original - the original subexpression
      replacement - the replacement subexpression
      Returns:
      true if the original subexpression is found
    • 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
    • process

      public void process(XPathContext context) throws XPathException
      Process this instruction, without leaving any tail calls.
      Specified by:
      process in interface Expression
      Overrides:
      process in class Instruction
      Parameters:
      context - the dynamic context for this transformation
      Throws:
      XPathException - if a dynamic error occurs
    • processLeavingTail

      public TailCall processLeavingTail(XPathContext context) throws XPathException
      Process this instruction. If the called template contains a tail call (which may be an xsl:call-template of xsl:apply-templates instruction) then the tail call will not actually be evaluated, but will be returned in a TailCall object for the caller to execute.
      Specified by:
      processLeavingTail in interface TailCallReturner
      Specified by:
      processLeavingTail in class Instruction
      Parameters:
      context - the dynamic context for this transformation
      Returns:
      an object containing information about the tail call to be executed by the caller. Returns null if there is no tail call.
      Throws:
      XPathException
    • getTargetTemplate

      public Template getTargetTemplate(XPathContext context) throws XPathException
      Get the template, in the case where it is specified dynamically.
      Parameters:
      context - The dynamic context of the transformation
      Returns:
      The template to be called
      Throws:
      XPathException - if a dynamic error occurs: specifically, if the template name is computed at run-time (Saxon extension) and the name is invalid or does not reference a known template
    • display

      public void display(int level, PrintStream out, Configuration config)
      Diagnostic print of expression structure. The expression is written to the System.err output stream
      Parameters:
      level - indentation level for this expression
      out -
      config -