Class IDPattern

java.lang.Object
net.sf.saxon.pattern.Pattern
net.sf.saxon.pattern.IDPattern
All Implemented Interfaces:
Serializable, SourceLocator, Container

public final class IDPattern extends Pattern
An IDPattern is a pattern of the form id("literal") or id($variable)
See Also:
  • Constructor Details

    • IDPattern

      public IDPattern(Expression id)
      Create an id pattern.
      Parameters:
      id - Either a StringValue or a VariableReference
  • Method Details

    • analyze

      public Pattern analyze(StaticContext env, ItemType contextItemType) throws XPathException
      Type-check the pattern. Default implementation does nothing. This is only needed for patterns that contain variable references or function calls.
      Overrides:
      analyze in class Pattern
      Returns:
      the optimised Pattern
      Throws:
      XPathException
    • getDependencies

      public int getDependencies()
      Get the dependencies of the pattern. The only possible dependency for a pattern is on local variables. This is analyzed in those patterns where local variables may appear.
      Overrides:
      getDependencies in class Pattern
    • iterateSubExpressions

      public Iterator iterateSubExpressions()
      Iterate over the subexpressions within this pattern
      Overrides:
      iterateSubExpressions in class Pattern
    • promote

      public void promote(PromotionOffer offer) throws XPathException
      Offer promotion for subexpressions within this pattern. 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.

      Unlike the corresponding method on Expression, this method does not return anything: it can make internal changes to the pattern, but cannot return a different pattern. Only certain kinds of promotion are applicable within a pattern: specifically, promotions affecting local variable references within the pattern.

      Overrides:
      promote in class Pattern
      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
    • matches

      public boolean matches(NodeInfo e, XPathContext context) throws XPathException
      Determine whether this Pattern matches the given Node
      Specified by:
      matches in class Pattern
      Parameters:
      e - The NodeInfo representing the Element or other node to be tested against the Pattern
      context - The dynamic context. Only relevant if the pattern uses variables, or contains calls on functions such as document() or key().
      Returns:
      true if the node matches the Pattern, false otherwise
      Throws:
      XPathException
    • getNodeKind

      public int getNodeKind()
      Determine the type of nodes to which this pattern applies.
      Overrides:
      getNodeKind in class Pattern
      Returns:
      Type.ELEMENT
    • getNodeTest

      public NodeTest getNodeTest()
      Get a NodeTest that all the nodes matching this pattern must satisfy
      Specified by:
      getNodeTest in class Pattern