Class Namespace

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

public class Namespace extends SimpleNodeConstructor
An xsl:namespace element in the stylesheet. (XSLT 2.0)
See Also:
  • Constructor Details

    • Namespace

      public Namespace(Expression name)
      Create an xsl:namespace instruction for dynamic construction of namespace nodes
      Parameters:
      name - the expression to evaluate the name of the node (that is, the prefix)
  • Method Details

    • getInstructionNameCode

      public int getInstructionNameCode()
      Set 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
      Description copied from class: Instruction
      Simplify an expression. This performs any static optimization (by rewriting the expression as a different expression). The default implementation does nothing.
      Overrides:
      simplify in class SimpleNodeConstructor
      Parameters:
      visitor - an expression visitor
      Returns:
      the simplified expression
      Throws:
      XPathException - if an error is discovered during expression rewriting
    • getItemType

      public ItemType getItemType(TypeHierarchy th)
      Description copied from class: Instruction
      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
    • getCardinality

      public int getCardinality()
      Description copied from class: Expression
      Determine the static cardinality of the expression. This establishes how many items there will be in the result of the expression, at compile time (i.e., without actually evaluating the result.
      Overrides:
      getCardinality in class Expression
      Returns:
      one of the values Cardinality.ONE_OR_MORE, Cardinality.ZERO_OR_MORE, Cardinality.EXACTLY_ONE, Cardinality.ZERO_OR_ONE, Cardinality.EMPTY. This default implementation returns ZERO_OR_MORE (which effectively gives no information).
    • promoteInst

      protected void promoteInst(PromotionOffer offer) throws XPathException
      Description copied from class: SimpleNodeConstructor
      Offer promotion for subexpressions. The offer will be accepted if the subexpression is not dependent on the factors (e.g. the context item) identified in the PromotionOffer. By default the offer is not accepted - this is appropriate in the case of simple expressions such as constant values and variable references where promotion would give no performance advantage. This method is always called at compile time.
      Overrides:
      promoteInst in class SimpleNodeConstructor
      Parameters:
      offer - details of the offer, for example the offer to move expressions that don't depend on the context to an outer level in the containing expression
      Throws:
      XPathException - if any error is detected
    • localTypeCheck

      public void localTypeCheck(ExpressionVisitor visitor, ItemType contextItemType)
      Description copied from class: SimpleNodeConstructor
      Method to perform type-checking specific to the kind of instruction
      Specified by:
      localTypeCheck in class SimpleNodeConstructor
      Parameters:
      visitor - an expression visitor
      contextItemType - the static type of the context item
    • iterateSubExpressions

      public Iterator iterateSubExpressions()
      Description copied from class: Expression
      Get the immediate sub-expressions of this expression. Default implementation returns a zero-length array, appropriate for an expression that has no sub-expressions.
      Overrides:
      iterateSubExpressions in class SimpleNodeConstructor
      Returns:
      an iterator containing the sub-expressions of this expression
    • 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
    • replaceSubExpression

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

      public int evaluateNameCode(XPathContext context) throws XPathException
      Description copied from class: SimpleNodeConstructor
      Run-time method to compute the name of the node being constructed. This is overridden for nodes that have a name. The default implementation returns -1, which is suitable for unnamed nodes such as comments
      Overrides:
      evaluateNameCode in class SimpleNodeConstructor
      Parameters:
      context - the XPath dynamic evaluation context
      Returns:
      the name pool nameCode identifying the name of the constructed node
      Throws:
      XPathException - if any failure occurs
    • 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
    • evaluateItem

      public Item evaluateItem(XPathContext context) throws XPathException
      Evaluate as an expression. We rely on the fact that when these instructions are generated by XQuery, there will always be a valueExpression to evaluate the content
      Specified by:
      evaluateItem in interface EvaluableItem
      Overrides:
      evaluateItem in class SimpleNodeConstructor
      Parameters:
      context - The context in which the expression is to be evaluated
      Returns:
      the node or atomic value that results from evaluating the expression; or null to indicate that the result is an empty sequence
      Throws:
      XPathException - if any dynamic error occurs evaluating the 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