Class TreeReceiver

java.lang.Object
net.sf.saxon.event.SequenceReceiver
net.sf.saxon.event.TreeReceiver
All Implemented Interfaces:
Result, Receiver
public class TreeReceiver extends SequenceReceiver
A TreeReceiver acts as a bridge between a SequenceReceiver, which can receive events for constructing any kind of sequence, and an ordinary Receiver, which only handles events relating to the building of trees. To do this, it has to process any items added to the sequence using the append() interface; all other events are passed through unchanged.

If atomic items are appended to the sequence, then adjacent atomic items are turned in to a text node by converting them to strings and adding a single space as a separator.

If a document node is appended to the sequence, then the document node is ignored and its children are appended to the sequence.

If any other node is appended to the sequence, then it is pushed to the result as a sequence of Receiver events, which may involve walking recursively through the contents of a tree.

  • Constructor Details

    • TreeReceiver

      public TreeReceiver(Receiver nextInChain)
      Create a TreeReceiver
      Parameters:
      nextInChain - the receiver to which events will be directed, after expanding append events into more primitive tree-based events

  • Method Details

    • setSystemId

      public void setSystemId(String systemId)
      Description copied from class: SequenceReceiver
      Set the system ID
      Specified by:
      setSystemId in interface Receiver
      Specified by:
      setSystemId in interface Result
      Overrides:
      setSystemId in class SequenceReceiver
      Parameters:
      systemId - the URI used to identify the tree being passed across this interface

    • setPipelineConfiguration

      public void setPipelineConfiguration(PipelineConfiguration pipe)
      Description copied from interface: Receiver
      Set the pipeline configuration
      Specified by:
      setPipelineConfiguration in interface Receiver
      Overrides:
      setPipelineConfiguration in class SequenceReceiver
      Parameters:
      pipe - the pipeline configuration

    • getUnderlyingReceiver

      public Receiver getUnderlyingReceiver()
      Get the underlying Receiver (that is, the next one in the pipeline)
      Returns:
      the underlying Receiver

    • open

      public void open() throws XPathException
      Start of event sequence
      Specified by:
      open in interface Receiver
      Overrides:
      open in class SequenceReceiver
      Throws:
      XPathException - if an error occurs

    • close

      public void close() throws XPathException
      End of event sequence
      Throws:
      XPathException - if an error occurs

    • startDocument

      public void startDocument(int properties) throws XPathException
      Start of a document node.
      Parameters:
      properties - bit-significant integer indicating properties of the document node. The definitions of the bits are in class ReceiverOptions
      Throws:
      XPathException - if an error occurs

    • endDocument

      public void endDocument() throws XPathException
      Notify the end of a document node
      Throws:
      XPathException - if an error occurs

    • startElement

      public void startElement(NodeName nameCode, SchemaType typeCode, int locationId, int properties) throws XPathException
      Notify the start of an element
      Parameters:
      nameCode - integer code identifying the name of the element within the name pool.
      typeCode - integer code identifying the element's type within the name pool.
      locationId - an integer which can be interpreted using a LocationProvider to return information such as line number and system ID. If no location information is available, the value zero is supplied.
      properties - bit-significant properties of the element node
      Throws:
      XPathException - if an error occurs

    • namespace

      public void namespace(NamespaceBinding namespaceBinding, int properties) throws XPathException
      Notify a namespace. Namespaces are notified after the startElement event, and before any children for the element. The namespaces that are reported are only required to include those that are different from the parent element; however, duplicates may be reported. A namespace must not conflict with any namespaces already used for element or attribute names.
      Parameters:
      namespaceBinding - the prefix/uri pair
      properties - The most important property is REJECT_DUPLICATES. If this property is set, the namespace declaration will be rejected if it conflicts with a previous declaration of the same prefix. If the property is not set, the namespace declaration will be ignored if it conflicts with a previous declaration. This reflects the fact that when copying a tree, namespaces for child elements are emitted before the namespaces of their parent element. Unfortunately this conflicts with the XSLT rule for complex content construction, where the recovery action in the event of conflicts is to take the namespace that comes last. XSLT therefore doesn't recover from this error:
      Throws:
      XPathException - if an error occurs

    • attribute

      public void attribute(NodeName nameCode, SimpleType typeCode, CharSequence value, int locationId, int properties) throws XPathException
      Notify an attribute. Attributes are notified after the startElement event, and before any children. Namespaces and attributes may be intermingled.
      Parameters:
      nameCode - The name of the attribute, as held in the name pool
      typeCode - The type of the attribute, as held in the name pool
      value - the string value of the attribute
      locationId - an integer which can be interpreted using a LocationProvider to return information such as line number and system ID. If no location information is available, the value zero is supplied.
      properties - Bit significant value. The following bits are defined:
      DISABLE_ESCAPING
      Disable escaping for this attribute
      NO_SPECIAL_CHARACTERS
      Attribute value contains no special characters
      Throws:
      XPathException - if an error occurs

    • startContent

      public void startContent() throws XPathException
      Notify the start of the content, that is, the completion of all attributes and namespaces. Note that the initial receiver of output from XSLT instructions will not receive this event, it has to detect it itself. Note that this event is reported for every element even if it has no attributes, no namespaces, and no content.
      Throws:
      XPathException - if an error occurs

    • endElement

      public void endElement() throws XPathException
      End of element
      Throws:
      XPathException - if an error occurs

    • characters

      public void characters(CharSequence chars, int locationId, int properties) throws XPathException
      Character data
      Parameters:
      chars - The characters
      locationId - an integer which can be interpreted using a LocationProvider to return information such as line number and system ID. If no location information is available, the value zero is supplied.
      properties - Bit significant value. The following bits are defined:
      DISABLE_ESCAPING
      Disable escaping for this text node
      USE_CDATA
      Output as a CDATA section
      Throws:
      XPathException - if an error occurs

    • processingInstruction

      public void processingInstruction(String target, CharSequence data, int locationId, int properties) throws XPathException
      Processing Instruction
      Parameters:
      target - The PI name. This must be a legal name (it will not be checked).
      data - The data portion of the processing instruction
      locationId - an integer which can be interpreted using a LocationProvider to return information such as line number and system ID. If no location information is available, the value zero is supplied.
      properties - Additional information about the PI.
      Throws:
      XPathException - if an error occurs

    • comment

      public void comment(CharSequence chars, int locationId, int properties) throws XPathException
      Output a comment
      Parameters:
      chars - The content of the comment
      locationId - an integer which can be interpreted using a LocationProvider to return information such as line number and system ID. If no location information is available, the value zero is supplied.
      properties - Additional information about the comment.
      Throws:
      XPathException - if an error occurs

    • setUnparsedEntity

      public void setUnparsedEntity(String name, String uri, String publicId) throws XPathException
      Set the URI for an unparsed entity in the document.
      Specified by:
      setUnparsedEntity in interface Receiver
      Overrides:
      setUnparsedEntity in class SequenceReceiver
      Parameters:
      name - The name of the unparsed entity
      uri - The system identifier of the unparsed entity
      publicId - The public identifier of the unparsed entity
      Throws:
      XPathException - if an error occurs

    • append

      public void append(Item item, int locationId, int copyNamespaces) throws XPathException
      Append an arbitrary item (node or atomic value) to the output
      Specified by:
      append in class SequenceReceiver
      Parameters:
      item - the item to be appended
      locationId - the location of the calling instruction, for diagnostics
      copyNamespaces - if the item is an element node, this indicates whether its namespaces need to be copied. Values are NodeInfo.ALL_NAMESPACES, NodeInfo.LOCAL_NAMESPACES, NodeInfo.NO_NAMESPACES
      Throws:
      XPathException - if the operation fails

    • usesTypeAnnotations

      public boolean usesTypeAnnotations()
      Ask whether this Receiver (or the downstream pipeline) makes any use of the type annotations supplied on element and attribute events
      Returns:
      true if the Receiver makes any use of this information. If false, the caller may supply untyped nodes instead of supplying the type annotation