org.dellroad.stuff.xml
Class AnnotatedXMLEventReader

java.lang.Object
  javax.xml.stream.util.EventReaderDelegate
      org.dellroad.stuff.xml.AnnotatedXMLEventReader

All Implemented Interfaces:

Iterator, XMLEventReader

Direct Known Subclasses:

UpdatesXMLEventReader

public abstract class AnnotatedXMLEventReader
extends EventReaderDelegate

XMLEventReader that reads and removes an initial annotation element from an XML document. The annotation element, if present, must be the first element inside the top-level document element. When the annotation element is encountered, readAnnotationElement() will be invoked.

This class can be used in combination with AnnotatedXMLEventWriter to transparently annotate XML documents.

See Also:

AnnotatedXMLEventWriter

Constructor Summary

AnnotatedXMLEventReader(XMLEventReader inner)
Constructor.

Method Summary

protected XMLEvent	advance() Advance one event in the event stream.
protected abstract boolean	isAnnotationElement(StartElement event) Determine if the given event represents the start of the annotation element.
Object	next()
XMLEvent	nextEvent()
XMLEvent	peek()
protected abstract void	readAnnotationElement(StartElement event) Read the annotation element.
void	setParent(XMLEventReader reader)
protected XMLEvent	skipWhiteSpace(XMLEvent event, boolean comments) Skip whitespace.

Methods inherited from class javax.xml.stream.util.EventReaderDelegate

close, getElementText, getParent, getProperty, hasNext, nextTag, remove

Methods inherited from class java.lang.Object

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

Constructor Detail

AnnotatedXMLEventReader

public AnnotatedXMLEventReader(XMLEventReader inner)

Constructor.

The given parameter should expect to read the XML document without the annotation element.

Parameters:

inner - nested reader

Method Detail

setParent

public void setParent(XMLEventReader reader)

Overrides:

setParent in class EventReaderDelegate

next

public Object next()

Specified by:

next in interface Iterator

Overrides:

next in class EventReaderDelegate

peek

public XMLEvent peek()
              throws XMLStreamException

Specified by:

peek in interface XMLEventReader

Overrides:

peek in class EventReaderDelegate

Throws:

XMLStreamException

nextEvent

public XMLEvent nextEvent()
                   throws XMLStreamException

Specified by:

nextEvent in interface XMLEventReader

Overrides:

nextEvent in class EventReaderDelegate

Throws:

XMLStreamException

isAnnotationElement

protected abstract boolean isAnnotationElement(StartElement event)

Determine if the given event represents the start of the annotation element.

readAnnotationElement

protected abstract void readAnnotationElement(StartElement event)
                                       throws XMLStreamException

Read the annotation element.

When this method is invoked, event represents the StartElement event for the annotation element (i.e., isAnnotationElement(event) has returned true); it is also the next event in the pipeline, i.e., the next event returned by nextEvent().

The last event consumed by this method should be the EndElement event for the annotation element, and the event returned by peek() should be the next event after the EndElement.

Parameters:

event - the StartElement event for the annotation element

Throws:

XMLStreamException

skipWhiteSpace

protected XMLEvent skipWhiteSpace(XMLEvent event,
                                  boolean comments)
                           throws XMLStreamException

Skip whitespace.

Parameters:

event - the next event, as returned by peek()

comments - whether to also skip comments

Returns:

the next event, as returned by peek(), after skipping any leading whitespace (and, optionally, comments)

Throws:

XMLStreamException

advance

protected XMLEvent advance()
                    throws XMLStreamException

Advance one event in the event stream.

Returns:

the next event, as returned by peek(), after the advance

Throws:

XMLStreamException