Package com.saxonica.ee.stream.adjunct

Class SequenceInstrAdjunct

java.lang.Object
com.saxonica.ee.stream.adjunct.StreamingAdjunct
com.saxonica.ee.stream.adjunct.SequenceInstrAdjunct
public class SequenceInstrAdjunct extends StreamingAdjunct

  • Constructor Details

    • SequenceInstrAdjunct

      public SequenceInstrAdjunct()

  • Method Details

    • toStreamingPattern

      public Pattern toStreamingPattern(Configuration config)
      Convert this expression to a streaming pattern (a pattern used internally to match nodes during push processing of an event stream)
      Overrides:
      toStreamingPattern in class StreamingAdjunct
      Parameters:
      config - the Saxon configuration
      Returns:
      the equivalent pattern if conversion succeeds; otherwise null

    • computeStreamability

      public PostureAndSweep computeStreamability(ContextItemStaticInfoEE contextInfo, List<String> reasons)
      Description copied from class: StreamingAdjunct
      Compute the posture and sweep of this expression as defined in the W3C streamability specifications. This must be implemented in all subclasses that don't use the general streamability rules. The implementation should have the side-effect of computing the streamability of all subexpressions, recursively.
      Overrides:
      computeStreamability in class StreamingAdjunct
      Parameters:
      contextInfo - Information about the context item type and posture
      reasons - the caller may supply a list, in which case the implementation may add to this; the contents are human-readable messages explaining why the expression is not streamable.
      Returns:
      the posture and sweep of the expression

    • getWatchMaker

      public WatchMaker getWatchMaker(boolean forGrouping) throws XPathException
      Description copied from class: StreamingAdjunct
      Get a WatchMaker, a factory class that creates a Watch to evaluate this expression in streaming mode. This method will only be called if the getImplementationMethod() method of the expression includes the value Expression.WATCH_METHOD
      Overrides:
      getWatchMaker in class StreamingAdjunct
      Parameters:
      forGrouping - true if the selected items are being grouped
      Returns:
      a Watchmaker to evaluate the expression, or null if it is not streamable with respect to the specificed argument.
      Throws:
      XPathException - in the event of a failure