net.sf.saxon.event
Class TreeReceiver

java.lang.Object
  extended by net.sf.saxon.event.SequenceReceiver
      extended by 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.


Field Summary
 
Fields inherited from class net.sf.saxon.event.SequenceReceiver
pipelineConfiguration, previousAtomic, systemId
 
Fields inherited from interface javax.xml.transform.Result
PI_DISABLE_OUTPUT_ESCAPING, PI_ENABLE_OUTPUT_ESCAPING
 
Constructor Summary
TreeReceiver(Receiver nextInChain)
          Create a TreeReceiver
 
Method Summary
 void append(Item item, int locationId, int copyNamespaces)
          Append an arbitrary item (node or atomic value) to the output
 void attribute(NodeName nameCode, SimpleType typeCode, CharSequence value, int locationId, int properties)
          Notify an attribute.
 void characters(CharSequence chars, int locationId, int properties)
          Character data
 void close()
          End of event sequence
 void comment(CharSequence chars, int locationId, int properties)
          Output a comment
 void endDocument()
          Notify the end of a document node
 void endElement()
          End of element
 Receiver getUnderlyingReceiver()
          Get the underlying Receiver (that is, the next one in the pipeline)
 void namespace(NamespaceBinding namespaceBinding, int properties)
          Notify a namespace.
 void open()
          Start of event sequence
 void processingInstruction(String target, CharSequence data, int locationId, int properties)
          Processing Instruction
 void setPipelineConfiguration(PipelineConfiguration pipe)
          Set the pipeline configuration
 void setSystemId(String systemId)
          Set the system ID
 void setUnparsedEntity(String name, String uri, String publicId)
          Set the URI for an unparsed entity in the document.
 void startContent()
          Notify the start of the content, that is, the completion of all attributes and namespaces.
 void startDocument(int properties)
          Start of a document node.
 void startElement(NodeName nameCode, SchemaType typeCode, int locationId, int properties)
          Notify the start of an element
 boolean usesTypeAnnotations()
          Ask whether this Receiver (or the downstream pipeline) makes any use of the type annotations supplied on element and attribute events
 
Methods inherited from class net.sf.saxon.event.SequenceReceiver
append, getConfiguration, getNamePool, getPipelineConfiguration, getSystemId
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

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 Detail

setSystemId

public void setSystemId(String systemId)
Description copied from class: SequenceReceiver
Set the system ID

Specified by:
setSystemId in interface Result
Specified by:
setSystemId in interface Receiver
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.
properties - bit-significant properties of the element node
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.
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:
IllegalStateException: - attempt to output a namespace when there is no open element start tag
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
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
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.
Throws:
IllegalStateException: - attempt to output an attribute when there is no open element start tag
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


Copyright (c) 2004-2011 Saxonica Limited. All rights reserved.