Class CallTemplate

java.lang.Object
net.sf.saxon.expr.Expression
net.sf.saxon.expr.instruct.Instruction
net.sf.saxon.expr.instruct.CallTemplate
All Implemented Interfaces:
Serializable, SourceLocator, LocationProvider, SaxonLocator, ITemplateCall, TailCallReturner, InstructionInfo, Locator
public class CallTemplate extends Instruction implements ITemplateCall
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 - true if the call is potentially tail recursive
      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

    • getCalledTemplateExpression

      public Expression getCalledTemplateExpression()

    • getNsContext

      public NamespaceResolver getNsContext()

    • setActualParameters

      public void setActualParameters(WithParam[] actualParams, WithParam[] tunnelParams)
      Set the actual parameters on the call
      Parameters:
      actualParams - the parameters that are not tunnel parameters
      tunnelParams - the tunnel parameters

    • getActualParams

      public WithParam[] getActualParams()
      Get the actual parameters passed to the called template
      Specified by:
      getActualParams in interface ITemplateCall
      Returns:
      the non-tunnel parameters

    • getTunnelParams

      public WithParam[] getTunnelParams()
      Get the tunnel parameters passed to the called template
      Specified by:
      getTunnelParams in interface ITemplateCall
      Returns:
      the tunnel parameters

    • getTargetTemplate

      public Template getTargetTemplate()
      Get the target template, if known statically
      Returns:
      the target template

    • usesTailRecursion

      public boolean usesTailRecursion()
      Ask whether this is a tail call
      Returns:
      true if this is a tail call

    • getInstructionNameCode

      public int getInstructionNameCode()
      Return the name of this instruction.
      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 - an expression visitor
      Returns:
      the simplified expression
      Throws:
      XPathException - if an error is discovered during expression rewriting

    • typeCheck

      public Expression typeCheck(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType 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 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, ExpressionVisitor.ContextItemType 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)

    • computeCardinality

      public int computeCardinality()
      Get the cardinality of the sequence returned by evaluating this instruction
      Overrides:
      computeCardinality in class Instruction
      Returns:
      the static cardinality

    • getItemType

      public ItemType getItemType(TypeHierarchy th)
      Get the item type of the items returned by evaluating this instruction
      Overrides:
      getItemType in class Instruction
      Parameters:
      th - the type hierarchy cache
      Returns:
      the static item type of the instruction

    • 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

    • getIntrinsicDependencies

      public int getIntrinsicDependencies()
      Description copied from class: Expression
      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 Expression
      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
      Returns:
      true if the instruction creates new nodes (or if it can't be proved that it doesn't)

    • iterateSubExpressions

      public Iterator<Expression> 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

    • 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

    • 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.
      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 - if a dynamic error occurs during the evaluation of the instruction

    • 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

    • getObjectName

      public StructuredQName getObjectName()
      Description copied from interface: InstructionInfo
      Get a name identifying the object of the expression, for example a function name, template name, variable name, key name, element name, etc. This is used only where the name is known statically.
      Specified by:
      getObjectName in interface InstructionInfo
      Overrides:
      getObjectName in class Expression
      Returns:
      the QName of the object declared or manipulated by this instruction or expression

    • 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 - the expression presenter used to display the structure