Class IncrementalSAXSource_Filter
- All Implemented Interfaces:
Runnable
,IncrementalSAXSource
,ContentHandler
,DTDHandler
,ErrorHandler
,LexicalHandler
IncrementalSAXSource_Filter implements IncrementalSAXSource, using a standard SAX2 event source as its input and parcelling out those events gradually in reponse to deliverMoreNodes() requests. Output from the filter will be passed along to a SAX handler registered as our listener, but those callbacks will pass through a counting stage which periodically yields control back to the controller coroutine.
%REVIEW%: This filter is not currenly intended to be reusable for parsing additional streams/documents. We may want to consider making it resettable at some point in the future. But it's a small object, so that'd be mostly a convenience issue; the cost of allocating each time is trivial compared to the cost of processing any nontrival stream.
For a brief usage example, see the unit-test main() method.
This is a simplification of the old CoroutineSAXParser, focusing specifically on filtering. The resulting controller protocol is _far_ simpler and less error-prone; the only controller operation is deliverMoreNodes(), and the only requirement is that deliverMoreNodes(false) be called if you want to discard the rest of the stream and the previous deliverMoreNodes() didn't return false.
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Constructor Summary
ConstructorsConstructorDescriptionIncrementalSAXSource_Filter
(CoroutineManager co, int controllerCoroutineID) Create a IncrementalSAXSource_Filter which is not yet bound to a specific SAX event source. -
Method Summary
Modifier and TypeMethodDescriptionvoid
characters
(char[] ch, int start, int length) void
comment
(char[] ch, int start, int length) static IncrementalSAXSource
createIncrementalSAXSource
(CoroutineManager co, int controllerCoroutineID) deliverMoreNodes
(boolean parsemore) deliverMoreNodes() is a simple API which tells the coroutine parser that we need more nodes.void
endCDATA()
void
void
endDTD()
void
endElement
(String namespaceURI, String localName, String qName) void
void
endPrefixMapping
(String prefix) void
error
(SAXParseException exception) void
fatalError
(SAXParseException exception) int
int
void
ignorableWhitespace
(char[] ch, int start, int length) void
init
(CoroutineManager co, int controllerCoroutineID, int sourceCoroutineID) void
notationDecl
(String a, String b, String c) void
processingInstruction
(String target, String data) void
run()
void
setContentHandler
(ContentHandler handler) Register a SAX-style content handler for us to output tovoid
setDocumentLocator
(Locator locator) void
setDTDHandler
(DTDHandler handler) Register a SAX-style DTD handler for us to output tovoid
setErrHandler
(ErrorHandler handler) void
setLexicalHandler
(LexicalHandler handler) Register a SAX-style lexical handler for us to output tovoid
setReturnFrequency
(int events) void
setXMLReader
(XMLReader eventsource) Bind our input streams to an XMLReader.void
skippedEntity
(String name) void
void
void
void
startElement
(String namespaceURI, String localName, String qName, Attributes atts) void
startEntity
(String name) void
startParse
(InputSource source) Launch a thread that will run an XMLReader's parse() operation within a thread, feeding events to this IncrementalSAXSource_Filter.void
startPrefixMapping
(String prefix, String uri) void
unparsedEntityDecl
(String a, String b, String c, String d) void
warning
(SAXParseException exception) Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Methods inherited from interface org.xml.sax.ContentHandler
declaration
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Constructor Details
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IncrementalSAXSource_Filter
public IncrementalSAXSource_Filter() -
IncrementalSAXSource_Filter
Create a IncrementalSAXSource_Filter which is not yet bound to a specific SAX event source.
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Method Details
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createIncrementalSAXSource
public static IncrementalSAXSource createIncrementalSAXSource(CoroutineManager co, int controllerCoroutineID) -
init
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setXMLReader
Bind our input streams to an XMLReader. Just a convenience routine; obviously you can explicitly register this as a listener with the same effect. -
setContentHandler
Description copied from interface:IncrementalSAXSource
Register a SAX-style content handler for us to output to- Specified by:
setContentHandler
in interfaceIncrementalSAXSource
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setDTDHandler
Description copied from interface:IncrementalSAXSource
Register a SAX-style DTD handler for us to output to- Specified by:
setDTDHandler
in interfaceIncrementalSAXSource
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setLexicalHandler
Description copied from interface:IncrementalSAXSource
Register a SAX-style lexical handler for us to output to- Specified by:
setLexicalHandler
in interfaceIncrementalSAXSource
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setErrHandler
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setReturnFrequency
public void setReturnFrequency(int events) -
characters
- Specified by:
characters
in interfaceContentHandler
- Throws:
SAXException
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endDocument
- Specified by:
endDocument
in interfaceContentHandler
- Throws:
SAXException
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endElement
- Specified by:
endElement
in interfaceContentHandler
- Throws:
SAXException
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endPrefixMapping
- Specified by:
endPrefixMapping
in interfaceContentHandler
- Throws:
SAXException
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ignorableWhitespace
- Specified by:
ignorableWhitespace
in interfaceContentHandler
- Throws:
SAXException
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processingInstruction
- Specified by:
processingInstruction
in interfaceContentHandler
- Throws:
SAXException
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setDocumentLocator
- Specified by:
setDocumentLocator
in interfaceContentHandler
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skippedEntity
- Specified by:
skippedEntity
in interfaceContentHandler
- Throws:
SAXException
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startDocument
- Specified by:
startDocument
in interfaceContentHandler
- Throws:
SAXException
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startElement
public void startElement(String namespaceURI, String localName, String qName, Attributes atts) throws SAXException - Specified by:
startElement
in interfaceContentHandler
- Throws:
SAXException
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startPrefixMapping
- Specified by:
startPrefixMapping
in interfaceContentHandler
- Throws:
SAXException
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comment
- Specified by:
comment
in interfaceLexicalHandler
- Throws:
SAXException
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endCDATA
- Specified by:
endCDATA
in interfaceLexicalHandler
- Throws:
SAXException
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endDTD
- Specified by:
endDTD
in interfaceLexicalHandler
- Throws:
SAXException
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endEntity
- Specified by:
endEntity
in interfaceLexicalHandler
- Throws:
SAXException
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startCDATA
- Specified by:
startCDATA
in interfaceLexicalHandler
- Throws:
SAXException
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startDTD
- Specified by:
startDTD
in interfaceLexicalHandler
- Throws:
SAXException
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startEntity
- Specified by:
startEntity
in interfaceLexicalHandler
- Throws:
SAXException
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notationDecl
- Specified by:
notationDecl
in interfaceDTDHandler
- Throws:
SAXException
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unparsedEntityDecl
- Specified by:
unparsedEntityDecl
in interfaceDTDHandler
- Throws:
SAXException
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error
- Specified by:
error
in interfaceErrorHandler
- Throws:
SAXException
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fatalError
- Specified by:
fatalError
in interfaceErrorHandler
- Throws:
SAXException
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warning
- Specified by:
warning
in interfaceErrorHandler
- Throws:
SAXException
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getSourceCoroutineID
public int getSourceCoroutineID() -
getControllerCoroutineID
public int getControllerCoroutineID() -
getCoroutineManager
- Returns:
- the CoroutineManager this CoroutineFilter object is bound to. If you're using the do...() methods, applications should only need to talk to the CoroutineManager once, to obtain the application's Coroutine ID.
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startParse
Launch a thread that will run an XMLReader's parse() operation within a thread, feeding events to this IncrementalSAXSource_Filter. Mostly a convenience routine, but has the advantage that -- since we invoked parse() -- we can halt parsing quickly via a StopException rather than waiting for the SAX stream to end by itself.- Specified by:
startParse
in interfaceIncrementalSAXSource
- Throws:
SAXException
- is parse thread is already in progress or parsing can not be started.
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run
public void run() -
deliverMoreNodes
deliverMoreNodes() is a simple API which tells the coroutine parser that we need more nodes. This is intended to be called from one of our partner routines, and serves to encapsulate the details of how incremental parsing has been achieved.- Specified by:
deliverMoreNodes
in interfaceIncrementalSAXSource
- Parameters:
parsemore
- If true, tells the incremental filter to generate another chunk of output. If false, tells the filter that we're satisfied and it can terminate parsing of this document.- Returns:
- Boolean.TRUE if there may be more events available by invoking deliverMoreNodes() again. Boolean.FALSE if parsing has run to completion (or been terminated by deliverMoreNodes(false). Or an exception object if something malfunctioned. %REVIEW% We _could_ actually throw the exception, but that would require runinng deliverMoreNodes() in a try/catch... and for many applications, exception will be simply be treated as "not TRUE" in any case.
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