com.saxonica.xqj.pull

Class PullFromIterator

java.lang.Object

com.saxonica.xqj.pull.PullFromIterator

All Implemented Interfaces:

PullProvider, UnfailingPullProvider

public class PullFromIterator
extends java.lang.Object
implements UnfailingPullProvider

This class delivers any XPath sequence through the pull interface. Atomic values in the sequence are supplied unchanged, as are top-level text, comment, attribute, namespace, and processing-instruction nodes. Elements and documents appearing in the input sequence are supplied as a sequence of events that walks recursively down the subtree rooted at that node. The input is supplied in the form of a SequenceIterator.

Field Summary

Fields inherited from interface net.sf.saxon.pull.PullProvider

ATOMIC_VALUE, ATTRIBUTE, COMMENT, END_DOCUMENT, END_ELEMENT, END_OF_INPUT, NAMESPACE, PROCESSING_INSTRUCTION, START_DOCUMENT, START_ELEMENT, START_OF_INPUT, TEXT

Constructor Summary

Constructors

Constructor and Description
PullFromIterator(SequenceIterator<?> base) Create a PullProvider that wraps a supplied SequenceIterator

Method Summary

Modifier and Type	Method and Description
void	close() Close the event reader.
int	current() Get the event most recently returned by next(), or by other calls that change the position, for example getStringValue() and skipToMatchingEnd().
AtomicValue	getAtomicValue() Get an atomic value.
AttributeCollection	getAttributes() Get the attributes associated with the current element.
NamespaceBinding[]	getNamespaceDeclarations() Get the namespace declarations associated with the current element.
NodeName	getNodeName() Get the NodeName identifying the name of the current node.
PipelineConfiguration	getPipelineConfiguration() Get configuration information.
SchemaType	getSchemaType() Get the type annotation of the current attribute or element node, or atomic value.
Location	getSourceLocator() Get the location of the current event.
java.lang.CharSequence	getStringValue() Get the string value of the current element, text node, processing-instruction, or top-level attribute or namespace node, or atomic value.
java.util.List<UnparsedEntity>	getUnparsedEntities() Get a list of unparsed entities.
int	next() Get the next event
void	setPipelineConfiguration(PipelineConfiguration pipe) Set configuration information.
int	skipToMatchingEnd() Skip the current subtree.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PullFromIterator

public PullFromIterator(SequenceIterator<?> base)

Create a PullProvider that wraps a supplied SequenceIterator

Parameters:

base - the sequence iterator to be wrapped

Method Detail

setPipelineConfiguration

public void setPipelineConfiguration(PipelineConfiguration pipe)

Set configuration information. This must only be called before any events have been read.

Specified by:

setPipelineConfiguration in interface PullProvider

Parameters:

pipe - the pipeline configuration

getPipelineConfiguration

public PipelineConfiguration getPipelineConfiguration()

Get configuration information.

Specified by:

getPipelineConfiguration in interface PullProvider

Returns:

the pipeline configuration

next

public int next()
         throws XPathException

Get the next event

Specified by:

next in interface PullProvider

Specified by:

next in interface UnfailingPullProvider

Returns:

an integer code indicating the type of event. The code PullProvider.END_OF_INPUT is returned at the end of the sequence.

Throws:

XPathException - if a dynamic error occurs

current

public int current()

Get the event most recently returned by next(), or by other calls that change the position, for example getStringValue() and skipToMatchingEnd(). This method does not change the position of the PullProvider.

Specified by:

current in interface PullProvider

Specified by:

current in interface UnfailingPullProvider

Returns:

the current event

getAttributes

public AttributeCollection getAttributes()

Get the attributes associated with the current element. This method must be called only after a START_ELEMENT event has been notified. The contents of the returned AttributeCollection are guaranteed to remain unchanged until the next START_ELEMENT event, but may be modified thereafter. The object should not be modified by the client.

Attributes may be read before or after reading the namespaces of an element, but must not be read after the first child node has been read, or after calling one of the methods skipToEnd(), getStringValue(), or getTypedValue().

Specified by:

getAttributes in interface PullProvider

Specified by:

getAttributes in interface UnfailingPullProvider

Returns:

an AttributeCollection representing the attributes of the element that has just been notified.

getNamespaceDeclarations

public NamespaceBinding[] getNamespaceDeclarations()

Get the namespace declarations associated with the current element. This method must be called only after a START_ELEMENT event has been notified. In the case of a top-level START_ELEMENT event (that is, an element that either has no parent node, or whose parent is not included in the sequence being read), the NamespaceDeclarations object returned will contain a namespace declaration for each namespace that is in-scope for this element node. In the case of a non-top-level element, the NamespaceDeclarations will contain a set of namespace declarations and undeclarations, representing the differences between this element and its parent.

It is permissible for this method to return namespace declarations that are redundant.

The NamespaceDeclarations object is guaranteed to remain unchanged until the next START_ELEMENT event, but may then be overwritten. The object should not be modified by the client.

Namespaces may be read before or after reading the attributes of an element, but must not be read after the first child node has been read, or after calling one of the methods skipToEnd(), getStringValue(), or getTypedValue().

Specified by:

getNamespaceDeclarations in interface PullProvider

Specified by:

getNamespaceDeclarations in interface UnfailingPullProvider

Returns:

the namespace declarations associated with the current START_ELEMENT event.

skipToMatchingEnd

public int skipToMatchingEnd()

Skip the current subtree. This method may be called only immediately after a START_DOCUMENT or START_ELEMENT event. This call returns the matching END_DOCUMENT or END_ELEMENT event; the next call on next() will return the event following the END_DOCUMENT or END_ELEMENT.

Specified by:

skipToMatchingEnd in interface PullProvider

Specified by:

skipToMatchingEnd in interface UnfailingPullProvider

Returns:

the matching END_DOCUMENT or END_ELEMENT event

close

public void close()

Close the event reader. This indicates that no further events are required. It is not necessary to close an event reader after PullProvider.END_OF_INPUT has been reported, but it is recommended to close it if reading terminates prematurely. Once an event reader has been closed, the effect of further calls on next() is undefined.

Specified by:

close in interface PullProvider

Specified by:

close in interface UnfailingPullProvider

getNodeName

public NodeName getNodeName()

Get the NodeName identifying the name of the current node. This method can be used after the PullProvider.START_ELEMENT, PullProvider.PROCESSING_INSTRUCTION, PullProvider.ATTRIBUTE, or PullProvider.NAMESPACE events. With some PullProvider implementations, it can also be used after PullProvider.END_ELEMENT, but this is not guaranteed: a client who requires the information at that point (for example, to do serialization) should insert an ElementNameTracker into the pipeline. If called at other times, the result is undefined and may result in an IllegalStateException. If called when the current node is an unnamed namespace node (a node representing the default namespace) the returned value is null.

Specified by:

getNodeName in interface PullProvider

Specified by:

getNodeName in interface UnfailingPullProvider

Returns:

the NodeName. The NodeName can be used to obtain the prefix, local name, and namespace URI.

getStringValue

public java.lang.CharSequence getStringValue()
                                      throws XPathException

Get the string value of the current element, text node, processing-instruction, or top-level attribute or namespace node, or atomic value.

In other situations the result is undefined and may result in an IllegalStateException.

If the most recent event was a PullProvider.START_ELEMENT, this method causes the content of the element to be read. The current event on completion of this method will be the corresponding PullProvider.END_ELEMENT. The next call of next() will return the event following the END_ELEMENT event.

Specified by:

getStringValue in interface PullProvider

Specified by:

getStringValue in interface UnfailingPullProvider

Returns:

the String Value of the node in question, defined according to the rules in the XPath data model.

Throws:

XPathException - if a dynamic error occurs

getAtomicValue

public AtomicValue getAtomicValue()

Get an atomic value. This call may be used only when the last event reported was ATOMIC_VALUE. This indicates that the PullProvider is reading a sequence that contains a free-standing atomic value; it is never used when reading the content of a node.

Specified by:

getAtomicValue in interface PullProvider

Specified by:

getAtomicValue in interface UnfailingPullProvider

Returns:

the atomic value

getSchemaType

public SchemaType getSchemaType()

Get the type annotation of the current attribute or element node, or atomic value. The result of this method is undefined unless the most recent event was START_ELEMENT, ATTRIBUTE, or ATOMIC_VALUE.

Specified by:

getSchemaType in interface PullProvider

Specified by:

getSchemaType in interface UnfailingPullProvider

Returns:

the type annotation.

getSourceLocator

public Location getSourceLocator()

Get the location of the current event. For an event stream representing a real document, the location information should identify the location in the lexical XML source. For a constructed document, it should identify the location in the query or stylesheet that caused the node to be created. A value of null can be returned if no location information is available.

Specified by:

getSourceLocator in interface PullProvider

Specified by:

getSourceLocator in interface UnfailingPullProvider

Returns:

the SourceLocator giving the location of the current event, or null if no location information is available

getUnparsedEntities

public java.util.List<UnparsedEntity> getUnparsedEntities()

Get a list of unparsed entities.

Specified by:

getUnparsedEntities in interface PullProvider

Specified by:

getUnparsedEntities in interface UnfailingPullProvider

Returns:

a list of unparsed entities, or null if the information is not available, or an empty list if there are no unparsed entities.