Class StreamWatch

java.lang.Object
com.saxonica.ee.stream.watch.AbstractWatch
com.saxonica.ee.stream.watch.StreamWatch
All Implemented Interfaces:
Watch

public class StreamWatch extends AbstractWatch
  • Constructor Details

  • Method Details

    • matchesNode

      public boolean matchesNode(FleetingNode node, XPathContext context) throws XPathException
      Determine whether the watch matches a given node
      Parameters:
      node - the node to be tested
      context - the XPath dynamic context
      Returns:
      true if the node is one of those the Watch is looking out for
      Throws:
      XPathException - if a dynamic error occurs
    • matchesNodesOfKind

      public boolean matchesNodesOfKind(UType kind)
      Ask whether the Watch is capable of matching nodes of a particular kind
      Parameters:
      kind - the node kind
      Returns:
      true if the watch is capabl of matching
    • setAnchorNode

      public void setAnchorNode(FleetingParentNode anchor)
      Set the anchor node for the watch. This is the node to which the watch is scoped, typically the context node for the streamable path expression that defines the root of the subtree within which nodes are being sought.
      Parameters:
      anchor - The anchor node within which the watch is scoped
    • getAnchorNode

      public FleetingParentNode getAnchorNode()
      Get the anchor node for the watch. This is the node to which the watch is scoped, typically the context node for the streamable path expression that defines the root of the subtree within which nodes are being sought.
      Returns:
      The anchor node within which the watch is scoped
    • startSelectedParentNode

      public Receiver startSelectedParentNode(FleetingParentNode node, Location locationId) throws XPathException
      Signal that an element or document node has been found that matches the selection that this Watch is looking for. This method is called by the WatchManager while processing the startElement or startDocument event that matches the selection.
      Parameters:
      node - the element or document node whose start event has been matched
      locationId - the location associated with the element or document node (may be the location of the instruction that created it)
      Returns:
      a Receiver to be notified of all events starting with the startElement/startDocument event for the matched element, and ending with the endElement event for that element; or null if this feature is not required.
      Throws:
      XPathException - May be raised if a dynamic error occurs
    • endSelectedParentNode

      public void endSelectedParentNode(Location locationId) throws XPathException
      Signal that the endElement event has occurred for the element whose startElement event caused the Watch to be activated.
      Parameters:
      locationId - the location of the element
      Throws:
      XPathException - May be raised if a constraint implemented by this Watch is violated