Package net.sf.saxon.expr.instruct

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:
ComponentInvocation, ContextOriginator, ExportAgent, ITemplateCall, Locatable, IdentityComparable, Traceable
public class CallTemplate extends Instruction implements ITemplateCall, ComponentInvocation
Instruction representing an xsl:call-template element in the stylesheet.

  • Constructor Details

    • CallTemplate

      public CallTemplate(NamedTemplate template, StructuredQName calledTemplateName, boolean useTailRecursion, boolean inStreamable)
      Construct a CallTemplate instruction.
      Parameters:
      template - the template to be called. This is provisional, and applies only if the template is not overridden in another package; the template supplied will be the one with matching name in the same package. Null in the case of saxon:call-template, and also in the case where the supplied name is xsl:original
      calledTemplateName - the name of the template to be called; null in the case of saxon:call-template where this is established dynamically
      useTailRecursion - true if the call is potentially tail recursive where the name of the called template is to be calculated dynamically
      inStreamable - true if the call-template instruction appears within a construct that is declared streamable, for example a streamable template rule

  • Method Details

    • 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

    • setTailRecursive

      public void setTailRecursive(boolean tailRecursive)
      Mark the instruction as tail-recursive (or not)
      Parameters:
      tailRecursive - true if the call appears in a tail position

    • getCalledTemplateName

      public StructuredQName getCalledTemplateName()
      Get the name (QName) of the template being called
      Returns:
      the name of the target template

    • getSymbolicName

      public SymbolicName getSymbolicName()
      Get the symbolic name of the template being called. This is essentially the component kind (template) plus the QName of the target template
      Specified by:
      getSymbolicName in interface ComponentInvocation
      Returns:
      the symbolic name of the target template, or null in the case of saxon:call-template where the name is defined dynamically

    • getTarget

      public Component getTarget()

    • getFixedTarget

      public Component getFixedTarget()
      Description copied from interface: ComponentInvocation
      Get the target component if this is known in advance, that is, if the target component is private or final, or in some other cases such as xsl:original. Otherwise, return null.
      Specified by:
      getFixedTarget in interface ComponentInvocation
      Returns:
      the bound component if the binding has been fixed

    • 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

    • setTargetTemplate

      public void setTargetTemplate(NamedTemplate target)
      Set the target template
      Parameters:
      target - the target template

    • getTargetTemplate

      public NamedTemplate getTargetTemplate()
      Get the target template
      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

    • setBindingSlot

      public void setBindingSlot(int slot)
      Set the binding slot to be used. This is the offset within the binding vector of the containing component where the actual target template is to be found. The target template is not held directly in the CallTemplate instruction itself because it can be overridden in a using package.
      Specified by:
      setBindingSlot in interface ComponentInvocation
      Parameters:
      slot - the offset in the binding vector of the containing package where the target template can be found.

    • getBindingSlot

      public int getBindingSlot()
      Get the binding slot to be used. This is the offset within the binding vector of the containing component where the actual target template is to be found.
      Specified by:
      getBindingSlot in interface ComponentInvocation
      Returns:
      the offset in the binding vector of the containing package where the target template can be found.

    • simplify

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

    • typeCheck

      public Expression typeCheck(ExpressionVisitor visitor, ContextItemStaticInfo contextInfo) 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.

      Overrides:
      typeCheck in class Expression
      Parameters:
      visitor - an expression visitor
      contextInfo - Information available statically about the context item: whether it is (possibly) absent; its static type; its streaming posture.
      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, ContextItemStaticInfo 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

      protected 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()
      Get the item type of the items returned by evaluating this instruction
      Overrides:
      getItemType in class Instruction
      Returns:
      the static item type of the instruction

    • copy

      public Expression copy(RebindingMap rebindings)
      Copy an expression. This makes a deep copy.
      Specified by:
      copy in class Expression
      Parameters:
      rebindings - Variables that need to be re-bound
      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:
      an integer containing bit-significant flags identifying the "intrinsic" dependencies. The flags are documented in class net.sf.saxon.value.StaticProperty

    • mayCreateNewNodes

      public final boolean mayCreateNewNodes()
      Determine whether this instruction creates new nodes. This implementation currently returns true unconditionally.
      Overrides:
      mayCreateNewNodes in class Instruction
      Returns:
      true if the instruction creates new nodes under some input conditions (or if it can't be proved that it doesn't)

    • operands

      public Iterable<Operand> operands()
      Description copied from class: Expression
      Get the immediate sub-expressions of this expression, with information about the relationship of each expression to its parent expression.

      If the expression is a Callable, then it is required that the order of the operands returned by this function is the same as the order of arguments supplied to the corresponding call() method.

      Specified by:
      operands in class Instruction
      Returns:
      an iterator containing the sub-expressions of this expression

    • process

      public void process(Outputter output, XPathContext context) throws XPathException
      Process this instruction, without leaving any tail calls.
      Overrides:
      process in class Instruction
      Parameters:
      output - the destination for the result
      context - the dynamic context for this transformation
      Throws:
      XPathException - if a dynamic error occurs

    • getObjectName

      public StructuredQName getObjectName()
      Description copied from interface: Traceable
      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 Traceable
      Overrides:
      getObjectName in class Expression
      Returns:
      the QName of the object declared or manipulated by this instruction or expression

    • export

      public void export(ExpressionPresenter out) throws XPathException
      Export of expression structure. The abstract expression tree is written to the supplied output destination.
      Specified by:
      export in interface ExportAgent
      Specified by:
      export in class Expression
      Parameters:
      out - the expression presenter used to display the structure
      Throws:
      XPathException - if the export fails, for example if an expression is found that won't work in the target environment.

    • toString

      public String toString()
      Description copied from class: Expression

      The toString() method for an expression attempts to give a representation of the expression in an XPath-like form.

      For subclasses of Expression that represent XPath expressions, the result should always be a string that parses as an XPath 3.0 expression. The expression produced should be equivalent to the original making certain assumptions about the static context. In general the expansion will make no assumptions about namespace bindings, except that (a) the prefix "xs" is used to refer to the XML Schema namespace, and (b) the default function namespace is assumed to be the "fn" namespace.

      In the case of XSLT instructions and XQuery expressions, the toString() method gives an abstracted view of the syntax that is not designed in general to be parseable.

      Overrides:
      toString in class Expression
      Returns:
      a representation of the expression as a string

    • toShortString

      public String toShortString()
      Description copied from class: Expression
      Produce a short string identifying the expression for use in error messages
      Overrides:
      toShortString in class Expression
      Returns:
      a short string, sufficient to identify the expression

    • getStreamerName

      public String getStreamerName()
      Description copied from class: Expression
      Get the (partial) name of a class that supports streaming of this kind of expression
      Overrides:
      getStreamerName in class Expression
      Returns:
      the partial name of a class that can be instantiated to provide streaming support in Saxon-EE, or null if there is no such class

    • getElaborator

      public Elaborator getElaborator()
      Make an elaborator for this expression
      Overrides:
      getElaborator in class Expression
      Returns:
      a suitable elaborator