DTMManagerDefaultpublic class DTMManagerDefault extends DTMManager The default implementation for the DTMManager.
%REVIEW% There is currently a reentrancy issue, since the finalizer
for XRTreeFrag (which runs in the GC thread) wants to call
DTMManager.release(), and may do so at the same time that the main
transformation thread is accessing the manager. Our current solution is
to make most of the manager's methods synchronized .
Early tests suggest that doing so is not causing a significant
performance hit in Xalan. However, it should be noted that there
is a possible alternative solution: rewrite release() so it merely
posts a request for release onto a threadsafe queue, and explicitly
process that queue on an infrequent basis during main-thread
activity (eg, when getDTM() is invoked). The downside of that solution
would be a greater delay before the DTM's storage is actually released
for reuse. |
Fields Summary |
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private static final boolean | DUMPTREESet this to true if you want a dump of the DTM after creation. | private static final boolean | DEBUGSet this to true if you want a basic diagnostics. | protected DTM[] | m_dtmsMap from DTM identifier numbers to DTM objects that this manager manages.
One DTM may have several prefix numbers, if extended node indexing
is in use; in that case, m_dtm_offsets[] will used to control which
prefix maps to which section of the DTM.
This array grows as necessary; see addDTM().
This array grows as necessary; see addDTM(). Growth is uncommon... but
access needs to be blindingly fast since it's used in node addressing. | int[] | m_dtm_offsetsMap from DTM identifier numbers to offsets. For small DTMs with a
single identifier, this will always be 0. In overflow addressing, where
additional identifiers are allocated to access nodes beyond the range of
a single Node Handle, this table is used to map the handle's node field
into the actual node identifier.
This array grows as necessary; see addDTM().
This array grows as necessary; see addDTM(). Growth is uncommon... but
access needs to be blindingly fast since it's used in node addressing.
(And at the moment, that includes accessing it from DTMDefaultBase,
which is why this is not Protected or Private.) | protected XMLReaderManager | m_readerManagerThe cache for XMLReader objects to be used if the user did not
supply an XMLReader for a SAXSource or supplied a StreamSource. | protected DefaultHandler | m_defaultHandlerThe default implementation of ContentHandler, DTDHandler and ErrorHandler. | private ExpandedNameTable | m_expandedNameTableThe default table for exandedNameID lookups. |
Constructors Summary |
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public DTMManagerDefault()Constructor DTMManagerDefault
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Methods Summary |
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public synchronized void | addDTM(com.sun.org.apache.xml.internal.dtm.DTM dtm, int id)Add a DTM to the DTM table. This convenience call adds it as the
"base DTM ID", with offset 0. The other version of addDTM should
be used if you want to add "extended" DTM IDs with nonzero offsets.
addDTM(dtm,id,0);
| public synchronized void | addDTM(com.sun.org.apache.xml.internal.dtm.DTM dtm, int id, int offset)Add a DTM to the DTM table.
if(id>=IDENT_MAX_DTMS)
{
// TODO: %REVIEW% Not really the right error message.
throw new DTMException(XMLMessages.createXMLMessage(XMLErrorResources.ER_NO_DTMIDS_AVAIL, null)); //"No more DTM IDs are available!");
}
// We used to just allocate the array size to IDENT_MAX_DTMS.
// But we expect to increase that to 16 bits, and I'm not willing
// to allocate that much space unless needed. We could use one of our
// handy-dandy Fast*Vectors, but this will do for now.
// %REVIEW%
int oldlen=m_dtms.length;
if(oldlen<=id)
{
// Various growth strategies are possible. I think we don't want
// to over-allocate excessively, and I'm willing to reallocate
// more often to get that. See also Fast*Vector classes.
//
// %REVIEW% Should throw a more diagnostic error if we go over the max...
int newlen=Math.min((id+256),IDENT_MAX_DTMS);
DTM new_m_dtms[] = new DTM[newlen];
System.arraycopy(m_dtms,0,new_m_dtms,0,oldlen);
m_dtms=new_m_dtms;
int new_m_dtm_offsets[] = new int[newlen];
System.arraycopy(m_dtm_offsets,0,new_m_dtm_offsets,0,oldlen);
m_dtm_offsets=new_m_dtm_offsets;
}
m_dtms[id] = dtm;
m_dtm_offsets[id]=offset;
dtm.documentRegistration();
// The DTM should have been told who its manager was when we created it.
// Do we need to allow for adopting DTMs _not_ created by this manager?
| public synchronized com.sun.org.apache.xml.internal.dtm.DTMIterator | createDTMIterator(int whatToShow, com.sun.org.apache.xml.internal.dtm.DTMFilter filter, boolean entityReferenceExpansion)NEEDSDOC Method createDTMIterator
NEEDSDOC @param whatToShow
NEEDSDOC @param filter
NEEDSDOC @param entityReferenceExpansion
NEEDSDOC (createDTMIterator) @return
/** @todo: implement this com.sun.org.apache.xml.internal.dtm.DTMManager abstract method */
return null;
| public synchronized com.sun.org.apache.xml.internal.dtm.DTMIterator | createDTMIterator(java.lang.String xpathString, com.sun.org.apache.xml.internal.utils.PrefixResolver presolver)NEEDSDOC Method createDTMIterator
NEEDSDOC @param xpathString
NEEDSDOC @param presolver
NEEDSDOC (createDTMIterator) @return
/** @todo: implement this com.sun.org.apache.xml.internal.dtm.DTMManager abstract method */
return null;
| public synchronized com.sun.org.apache.xml.internal.dtm.DTMIterator | createDTMIterator(int node)NEEDSDOC Method createDTMIterator
NEEDSDOC @param node
NEEDSDOC (createDTMIterator) @return
/** @todo: implement this com.sun.org.apache.xml.internal.dtm.DTMManager abstract method */
return null;
| public synchronized com.sun.org.apache.xml.internal.dtm.DTMIterator | createDTMIterator(java.lang.Object xpathCompiler, int pos)NEEDSDOC Method createDTMIterator
NEEDSDOC @param xpathCompiler
NEEDSDOC @param pos
NEEDSDOC (createDTMIterator) @return
/** @todo: implement this com.sun.org.apache.xml.internal.dtm.DTMManager abstract method */
return null;
| public synchronized com.sun.org.apache.xml.internal.dtm.DTM | createDocumentFragment()Method createDocumentFragment
NEEDSDOC (createDocumentFragment) @return
try
{
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
dbf.setNamespaceAware(true);
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.newDocument();
Node df = doc.createDocumentFragment();
return getDTM(new DOMSource(df), true, null, false, false);
}
catch (Exception e)
{
throw new DTMException(e);
}
| public synchronized com.sun.org.apache.xml.internal.dtm.DTM | getDTM(javax.xml.transform.Source source, boolean unique, com.sun.org.apache.xml.internal.dtm.DTMWSFilter whiteSpaceFilter, boolean incremental, boolean doIndexing)Get an instance of a DTM, loaded with the content from the
specified source. If the unique flag is true, a new instance will
always be returned. Otherwise it is up to the DTMManager to return a
new instance or an instance that it already created and may be being used
by someone else.
A bit of magic in this implementation: If the source is null, unique is true,
and incremental and doIndexing are both false, we return an instance of
SAX2RTFDTM, which see.
(I think more parameters will need to be added for error handling, and entity
resolution, and more explicit control of the RTF situation).
if(DEBUG && null != source)
System.out.println("Starting "+
(unique ? "UNIQUE" : "shared")+
" source: "+source.getSystemId()
);
XMLStringFactory xstringFactory = m_xsf;
int dtmPos = getFirstFreeDTMID();
int documentID = dtmPos << IDENT_DTM_NODE_BITS;
if ((null != source) && source instanceof DOMSource)
{
DOM2DTM dtm = new DOM2DTM(this, (DOMSource) source, documentID,
whiteSpaceFilter, xstringFactory, doIndexing);
addDTM(dtm, dtmPos, 0);
// if (DUMPTREE)
// {
// dtm.dumpDTM();
// }
return dtm;
}
else
{
boolean isSAXSource = (null != source)
? (source instanceof SAXSource) : true;
boolean isStreamSource = (null != source)
? (source instanceof StreamSource) : false;
if (isSAXSource || isStreamSource) {
XMLReader reader = null;
SAX2DTM dtm;
try {
InputSource xmlSource;
if (null == source) {
xmlSource = null;
} else {
reader = getXMLReader(source);
xmlSource = SAXSource.sourceToInputSource(source);
String urlOfSource = xmlSource.getSystemId();
if (null != urlOfSource) {
try {
urlOfSource = SystemIDResolver.getAbsoluteURI(urlOfSource);
} catch (Exception e) {
// %REVIEW% Is there a better way to send a warning?
System.err.println("Can not absolutize URL: " + urlOfSource);
}
xmlSource.setSystemId(urlOfSource);
}
}
if (source==null && unique && !incremental && !doIndexing) {
// Special case to support RTF construction into shared DTM.
// It should actually still work for other uses,
// but may be slightly deoptimized relative to the base
// to allow it to deal with carrying multiple documents.
//
// %REVIEW% This is a sloppy way to request this mode;
// we need to consider architectural improvements.
dtm = new SAX2RTFDTM(this, source, documentID, whiteSpaceFilter,
xstringFactory, doIndexing);
}
/**************************************************************
// EXPERIMENTAL 3/22/02
else if(JKESS_XNI_EXPERIMENT && m_incremental) {
dtm = new XNI2DTM(this, source, documentID, whiteSpaceFilter,
xstringFactory, doIndexing);
}
**************************************************************/
// Create the basic SAX2DTM.
else {
dtm = new SAX2DTM(this, source, documentID, whiteSpaceFilter,
xstringFactory, doIndexing);
}
// Go ahead and add the DTM to the lookup table. This needs to be
// done before any parsing occurs. Note offset 0, since we've just
// created a new DTM.
addDTM(dtm, dtmPos, 0);
boolean haveXercesParser =
(null != reader)
&& (reader.getClass()
.getName()
.equals("com.sun.org.apache.xerces.internal.parsers.SAXParser") );
if (haveXercesParser) {
incremental = true; // No matter what. %REVIEW%
}
// If the reader is null, but they still requested an incremental
// build, then we still want to set up the IncrementalSAXSource stuff.
if (m_incremental && incremental
/* || ((null == reader) && incremental) */) {
IncrementalSAXSource coParser=null;
if (haveXercesParser) {
// IncrementalSAXSource_Xerces to avoid threading.
try {
coParser =(IncrementalSAXSource)
Class.forName("com.sun.org.apache.xml.internal.dtm.ref.IncrementalSAXSource_Xerces").newInstance();
} catch( Exception ex ) {
ex.printStackTrace();
coParser=null;
}
}
if (coParser==null ) {
// Create a IncrementalSAXSource to run on the secondary thread.
if (null == reader) {
coParser = new IncrementalSAXSource_Filter();
} else {
IncrementalSAXSource_Filter filter =
new IncrementalSAXSource_Filter();
filter.setXMLReader(reader);
coParser=filter;
}
}
/**************************************************************
// EXPERIMENTAL 3/22/02
if (JKESS_XNI_EXPERIMENT && m_incremental &&
dtm instanceof XNI2DTM &&
coParser instanceof IncrementalSAXSource_Xerces) {
com.sun.org.apache.xerces.internal.xni.parser.XMLPullParserConfiguration xpc=
((IncrementalSAXSource_Xerces)coParser)
.getXNIParserConfiguration();
if (xpc!=null) {
// Bypass SAX; listen to the XNI stream
((XNI2DTM)dtm).setIncrementalXNISource(xpc);
} else {
// Listen to the SAX stream (will fail, diagnostically...)
dtm.setIncrementalSAXSource(coParser);
}
} else
***************************************************************/
// Have the DTM set itself up as IncrementalSAXSource's listener.
dtm.setIncrementalSAXSource(coParser);
if (null == xmlSource) {
// Then the user will construct it themselves.
return dtm;
}
if (null == reader.getErrorHandler()) {
reader.setErrorHandler(dtm);
}
reader.setDTDHandler(dtm);
try {
// Launch parsing coroutine. Launches a second thread,
// if we're using IncrementalSAXSource.filter().
coParser.startParse(xmlSource);
} catch (RuntimeException re) {
dtm.clearCoRoutine();
throw re;
} catch (Exception e) {
dtm.clearCoRoutine();
throw new com.sun.org.apache.xml.internal.utils.WrappedRuntimeException(e);
}
} else {
if (null == reader) {
// Then the user will construct it themselves.
return dtm;
}
// not incremental
reader.setContentHandler(dtm);
reader.setDTDHandler(dtm);
if (null == reader.getErrorHandler()) {
reader.setErrorHandler(dtm);
}
try {
reader.setProperty(
"http://xml.org/sax/properties/lexical-handler",
dtm);
} catch (SAXNotRecognizedException e){}
catch (SAXNotSupportedException e){}
try {
reader.parse(xmlSource);
} catch (RuntimeException re) {
dtm.clearCoRoutine();
throw re;
} catch (Exception e) {
dtm.clearCoRoutine();
throw new com.sun.org.apache.xml.internal.utils.WrappedRuntimeException(e);
}
}
if (DUMPTREE) {
System.out.println("Dumping SAX2DOM");
dtm.dumpDTM(System.err);
}
return dtm;
} finally {
// Reset the ContentHandler, DTDHandler, ErrorHandler to the DefaultHandler
// after creating the DTM.
if (reader != null && !(m_incremental && incremental)) {
reader.setContentHandler(m_defaultHandler);
reader.setDTDHandler(m_defaultHandler);
reader.setErrorHandler(m_defaultHandler);
// Reset the LexicalHandler to null after creating the DTM.
try {
reader.setProperty("http://xml.org/sax/properties/lexical-handler", null);
}
catch (Exception e) {}
}
releaseXMLReader(reader);
}
} else {
// It should have been handled by a derived class or the caller
// made a mistake.
throw new DTMException(XMLMessages.createXMLMessage(XMLErrorResources.ER_NOT_SUPPORTED, new Object[]{source})); //"Not supported: " + source);
}
}
| public synchronized com.sun.org.apache.xml.internal.dtm.DTM | getDTM(int nodeHandle)Return the DTM object containing a representation of this node.
try
{
// Performance critical function.
return m_dtms[nodeHandle >>> IDENT_DTM_NODE_BITS];
}
catch(java.lang.ArrayIndexOutOfBoundsException e)
{
if(nodeHandle==DTM.NULL)
return null; // Accept as a special case.
else
throw e; // Programming error; want to know about it.
}
| public synchronized int | getDTMHandleFromNode(org.w3c.dom.Node node)Given a W3C DOM node, try and return a DTM handle.
Note: calling this may be non-optimal, and there is no guarantee that
the node will be found in any particular DTM.
if(null == node)
throw new IllegalArgumentException(XMLMessages.createXMLMessage(XMLErrorResources.ER_NODE_NON_NULL, null)); //"node must be non-null for getDTMHandleFromNode!");
if (node instanceof com.sun.org.apache.xml.internal.dtm.ref.DTMNodeProxy)
return ((com.sun.org.apache.xml.internal.dtm.ref.DTMNodeProxy) node).getDTMNodeNumber();
else
{
// Find the DOM2DTMs wrapped around this Document (if any)
// and check whether they contain the Node in question.
//
// NOTE that since a DOM2DTM may represent a subtree rather
// than a full document, we have to be prepared to check more
// than one -- and there is no guarantee that we will find
// one that contains ancestors or siblings of the node we're
// seeking.
//
// %REVIEW% We could search for the one which contains this
// node at the deepest level, and thus covers the widest
// subtree, but that's going to entail additional work
// checking more DTMs... and getHandleOfNode is not a
// cheap operation in most implementations.
//
// TODO: %REVIEW% If overflow addressing, we may recheck a DTM
// already examined. Ouch. But with the increased number of DTMs,
// scanning back to check this is painful.
// POSSIBLE SOLUTIONS:
// Generate a list of _unique_ DTM objects?
// Have each DTM cache last DOM node search?
int max = m_dtms.length;
for(int i = 0; i < max; i++)
{
DTM thisDTM=m_dtms[i];
if((null != thisDTM) && thisDTM instanceof DOM2DTM)
{
int handle=((DOM2DTM)thisDTM).getHandleOfNode(node);
if(handle!=DTM.NULL) return handle;
}
}
// Not found; generate a new DTM.
//
// %REVIEW% Is this really desirable, or should we return null
// and make folks explicitly instantiate from a DOMSource? The
// latter is more work but gives the caller the opportunity to
// explicitly add the DTM to a DTMManager... and thus to know when
// it can be discarded again, which is something we need to pay much
// more attention to. (Especially since only DTMs which are assigned
// to a manager can use the overflow addressing scheme.)
//
// %BUG% If the source node was a DOM2DTM$defaultNamespaceDeclarationNode
// and the DTM wasn't registered with this DTMManager, we will create
// a new DTM and _still_ not be able to find the node (since it will
// be resynthesized). Another reason to push hard on making all DTMs
// be managed DTMs.
// Since the real root of our tree may be a DocumentFragment, we need to
// use getParent to find the root, instead of getOwnerDocument. Otherwise
// DOM2DTM#getHandleOfNode will be very unhappy.
Node root = node;
Node p = (root.getNodeType() == Node.ATTRIBUTE_NODE) ? ((org.w3c.dom.Attr)root).getOwnerElement() : root.getParentNode();
for (; p != null; p = p.getParentNode())
{
root = p;
}
DOM2DTM dtm = (DOM2DTM) getDTM(new javax.xml.transform.dom.DOMSource(root),
false, null, true, true);
int handle;
if(node instanceof com.sun.org.apache.xml.internal.dtm.ref.dom2dtm.DOM2DTMdefaultNamespaceDeclarationNode)
{
// Can't return the same node since it's unique to a specific DTM,
// but can return the equivalent node -- find the corresponding
// Document Element, then ask it for the xml: namespace decl.
handle=dtm.getHandleOfNode(((org.w3c.dom.Attr)node).getOwnerElement());
handle=dtm.getAttributeNode(handle,node.getNamespaceURI(),node.getLocalName());
}
else
handle = ((DOM2DTM)dtm).getHandleOfNode(node);
if(DTM.NULL == handle)
throw new RuntimeException(XMLMessages.createXMLMessage(XMLErrorResources.ER_COULD_NOT_RESOLVE_NODE, null)); //"Could not resolve the node to a handle!");
return handle;
}
| public synchronized int | getDTMIdentity(com.sun.org.apache.xml.internal.dtm.DTM dtm)Given a DTM, find the ID number in the DTM tables which addresses
the start of the document. If overflow addressing is in use, other
DTM IDs may also be assigned to this DTM.
// Shortcut using DTMDefaultBase's extension hooks
// %REVIEW% Should the lookup be part of the basic DTM API?
if(dtm instanceof DTMDefaultBase)
{
DTMDefaultBase dtmdb=(DTMDefaultBase)dtm;
if(dtmdb.getManager()==this)
return dtmdb.getDTMIDs().elementAt(0);
else
return -1;
}
int n = m_dtms.length;
for (int i = 0; i < n; i++)
{
DTM tdtm = m_dtms[i];
if (tdtm == dtm && m_dtm_offsets[i]==0)
return i << IDENT_DTM_NODE_BITS;
}
return -1;
| public com.sun.org.apache.xml.internal.dtm.ref.ExpandedNameTable | getExpandedNameTable(com.sun.org.apache.xml.internal.dtm.DTM dtm)return the expanded name table.
NEEDSDOC @param dtm
NEEDSDOC ($objectName$) @return
return m_expandedNameTable;
| public synchronized int | getFirstFreeDTMID()Get the first free DTM ID available. %OPT% Linear search is inefficient!
int n = m_dtms.length;
for (int i = 1; i < n; i++)
{
if(null == m_dtms[i])
{
return i;
}
}
return n; // count on addDTM() to throw exception if out of range
| public synchronized org.xml.sax.XMLReader | getXMLReader(javax.xml.transform.Source inputSource)This method returns the SAX2 parser to use with the InputSource
obtained from this URI.
It may return null if any SAX2-conformant XML parser can be used,
or if getInputSource() will also return null. The parser must
be free for use (i.e., not currently in use for another parse().
After use of the parser is completed, the releaseXMLReader(XMLReader)
must be called.
try
{
XMLReader reader = (inputSource instanceof SAXSource)
? ((SAXSource) inputSource).getXMLReader() : null;
// If user did not supply a reader, ask for one from the reader manager
if (null == reader) {
if (m_readerManager == null) {
m_readerManager = XMLReaderManager.getInstance();
}
reader = m_readerManager.getXMLReader();
}
return reader;
} catch (SAXException se) {
throw new DTMException(se.getMessage(), se);
}
| public synchronized boolean | release(com.sun.org.apache.xml.internal.dtm.DTM dtm, boolean shouldHardDelete)Release the DTMManager's reference(s) to a DTM, making it unmanaged.
This is typically done as part of returning the DTM to the heap after
we're done with it.
if(DEBUG)
{
System.out.println("Releasing "+
(shouldHardDelete ? "HARD" : "soft")+
" dtm="+
// Following shouldn't need a nodeHandle, but does...
// and doesn't seem to report the intended value
dtm.getDocumentBaseURI()
);
}
if (dtm instanceof SAX2DTM)
{
((SAX2DTM) dtm).clearCoRoutine();
}
// Multiple DTM IDs may be assigned to a single DTM.
// The Right Answer is to ask which (if it supports
// extension, the DTM will need a list anyway). The
// Wrong Answer, applied if the DTM can't help us,
// is to linearly search them all; this may be very
// painful.
//
// %REVIEW% Should the lookup move up into the basic DTM API?
if(dtm instanceof DTMDefaultBase)
{
com.sun.org.apache.xml.internal.utils.SuballocatedIntVector ids=((DTMDefaultBase)dtm).getDTMIDs();
for(int i=ids.size()-1;i>=0;--i)
m_dtms[ids.elementAt(i)>>>DTMManager.IDENT_DTM_NODE_BITS]=null;
}
else
{
int i = getDTMIdentity(dtm);
if (i >= 0)
{
m_dtms[i >>> DTMManager.IDENT_DTM_NODE_BITS] = null;
}
}
dtm.documentRelease();
return true;
| public synchronized void | releaseXMLReader(org.xml.sax.XMLReader reader)Indicates that the XMLReader object is no longer in use for the transform.
Note that the getXMLReader method may return an XMLReader that was
specified on the SAXSource object by the application code. Such a
reader should still be passed to releaseXMLReader, but the reader manager
will only re-use XMLReaders that it created.
if (m_readerManager != null) {
m_readerManager.releaseXMLReader(reader);
}
|
|