/*
* The Apache Software License, Version 1.1
*
*
* Copyright (c) 1999 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Xalan" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation and was
* originally based on software copyright (c) 1999, Lotus
* Development Corporation., http://www.lotus.com. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/
package org.apache.xpath.axes;
// Java library imports
import java.util.Vector;
import java.util.Stack;
import org.apache.xml.dtm.DTM;
import org.apache.xml.dtm.DTMIterator;
import org.apache.xml.dtm.DTMFilter;
import org.apache.xml.dtm.DTMManager;
// Xalan imports
import org.apache.xpath.res.XPATHErrorResources;
import org.apache.xpath.XPath;
import org.apache.xpath.compiler.OpMap;
import org.apache.xpath.compiler.Compiler;
import org.apache.xpath.compiler.OpCodes;
import org.apache.xpath.compiler.PsuedoNames;
import org.apache.xpath.NodeSetDTM;
import org.apache.xpath.Expression;
import org.apache.xpath.XPathContext;
import org.apache.xpath.objects.XObject;
import org.apache.xml.utils.IntStack;
import org.apache.xml.utils.PrefixResolver;
import org.apache.xml.utils.ObjectPool;
import org.apache.xpath.objects.XNodeSet;
import org.apache.xpath.axes.AxesWalker;
import org.apache.xpath.VariableStack;
/**
* <meta name="usage" content="advanced"/>
* This class extends NodeSetDTM, which implements NodeIterator,
* and fetches nodes one at a time in document order based on a XPath
* <a href="http://www.w3.org/TR/xpath#NT-LocationPath>LocationPath</a>.
*
* <p>If setShouldCacheNodes(true) is called,
* as each node is iterated via nextNode(), the node is also stored
* in the NodeVector, so that previousNode() can easily be done, except in
* the case where the LocPathIterator is "owned" by a UnionPathIterator,
* in which case the UnionPathIterator will cache the nodes.</p>
*/
public abstract class LocPathIterator extends PredicatedNodeTest
implements Cloneable, DTMIterator, java.io.Serializable
{
/**
* Create a LocPathIterator object.
*
* @param nscontext The namespace context for this iterator,
* should be OK if null.
*/
protected LocPathIterator(PrefixResolver nscontext)
{
setLocPathIterator(this);
this.m_prefixResolver = nscontext;
}
/**
* Create a LocPathIterator object, including creation
* of step walkers from the opcode list, and call back
* into the Compiler to create predicate expressions.
*
* @param compiler The Compiler which is creating
* this expression.
* @param opPos The position of this iterator in the
* opcode list from the compiler.
*
* @throws javax.xml.transform.TransformerException
*/
protected LocPathIterator(Compiler compiler, int opPos, int analysis)
throws javax.xml.transform.TransformerException
{
this(compiler, opPos, analysis, true);
}
/**
* Create a LocPathIterator object, including creation
* of step walkers from the opcode list, and call back
* into the Compiler to create predicate expressions.
*
* @param compiler The Compiler which is creating
* this expression.
* @param opPos The position of this iterator in the
* opcode list from the compiler.
* @param shouldLoadWalkers True if walkers should be
* loaded, or false if this is a derived iterator and
* it doesn't wish to load child walkers.
*
* @throws javax.xml.transform.TransformerException
*/
protected LocPathIterator(
Compiler compiler, int opPos, int analysis, boolean shouldLoadWalkers)
throws javax.xml.transform.TransformerException
{
setLocPathIterator(this);
}
/**
* Read the object from a serialization stream.
*
* @param stream Input stream to read from
*
* @throws java.io.IOException
* @throws javax.xml.transform.TransformerException
*/
private void readObject(java.io.ObjectInputStream stream)
throws java.io.IOException, javax.xml.transform.TransformerException
{
try
{
stream.defaultReadObject();
m_clones = new IteratorPool(this);
}
catch (ClassNotFoundException cnfe)
{
throw new javax.xml.transform.TransformerException(cnfe);
}
}
/**
* Set the environment in which this iterator operates, which should provide:
* a node (the context node... same value as "root" defined below)
* a pair of non-zero positive integers (the context position and the context size)
* a set of variable bindings
* a function library
* the set of namespace declarations in scope for the expression.
*
* <p>At this time the exact implementation of this environment is application
* dependent. Probably a proper interface will be created fairly soon.</p>
*
* @param environment The environment object.
*/
public void setEnvironment(Object environment)
{
// no-op for now.
}
/**
* Get an instance of a DTM that "owns" a node handle. Since a node
* iterator may be passed without a DTMManager, this allows the
* caller to easily get the DTM using just the iterator.
*
* @param nodeHandle the nodeHandle.
*
* @return a non-null DTM reference.
*/
public DTM getDTM(int nodeHandle)
{
// %OPT%
return m_execContext.getDTM(nodeHandle);
}
/**
* Get an instance of the DTMManager. Since a node
* iterator may be passed without a DTMManager, this allows the
* caller to easily get the DTMManager using just the iterator.
*
* @return a non-null DTMManager reference.
*/
public DTMManager getDTMManager()
{
return m_execContext.getDTMManager();
}
/**
* Execute this iterator, meaning create a clone that can
* store state, and initialize it for fast execution from
* the current runtime state. When this is called, no actual
* query from the current context node is performed.
*
* @param xctxt The XPath execution context.
*
* @return An XNodeSet reference that holds this iterator.
*
* @throws javax.xml.transform.TransformerException
*/
public XObject execute(XPathContext xctxt)
throws javax.xml.transform.TransformerException
{
LocPathIterator clone = (LocPathIterator)m_clones.getInstance();
int current = xctxt.getCurrentNode();
clone.setRoot(current, xctxt);
return new XNodeSet(clone);
}
/**
* <meta name="usage" content="experimental"/>
* Given an select expression and a context, evaluate the XPath
* and return the resulting iterator.
*
* @param xctxt The execution context.
* @param contextNode The node that "." expresses.
* @param namespaceContext The context in which namespaces in the
* XPath are supposed to be expanded.
*
* @throws TransformerException thrown if the active ProblemListener decides
* the error condition is severe enough to halt processing.
*
* @throws javax.xml.transform.TransformerException
*/
public DTMIterator asIterator(
XPathContext xctxt, int contextNode)
throws javax.xml.transform.TransformerException
{
LocPathIterator clone = (LocPathIterator)m_clones.getInstance();
clone.setRoot(contextNode, xctxt);
return clone;
}
/**
* Tell if the expression is a nodeset expression. In other words, tell
* if you can execute {@link asNode() asNode} without an exception.
* @return true if the expression can be represented as a nodeset.
*/
public boolean isNodesetExpr()
{
return true;
}
/**
* Return the first node out of the nodeset, if this expression is
* a nodeset expression. This is the default implementation for
* nodesets. Derived classes should try and override this and return a
* value without having to do a clone operation.
* @param xctxt The XPath runtime context.
* @return the first node out of the nodeset, or DTM.NULL.
*/
public int asNode(XPathContext xctxt)
throws javax.xml.transform.TransformerException
{
DTMIterator iter = (DTMIterator)m_clones.getInstance();
int current = xctxt.getCurrentNode();
iter.setRoot(current, xctxt);
int next = iter.nextNode();
// m_clones.freeInstance(iter);
iter.detach();
return next;
}
/**
* Evaluate this operation directly to a boolean.
*
* @param xctxt The runtime execution context.
*
* @return The result of the operation as a boolean.
*
* @throws javax.xml.transform.TransformerException
*/
public boolean bool(XPathContext xctxt)
throws javax.xml.transform.TransformerException
{
return (asNode(xctxt) != DTM.NULL);
}
/**
* <meta name="usage" content="advanced"/>
* Set if this is an iterator at the upper level of
* the XPath.
*
* @param b true if this location path is at the top level of the
* expression.
*/
public void setIsTopLevel(boolean b)
{
m_isTopLevel = b;
}
/**
* <meta name="usage" content="advanced"/>
* Get if this is an iterator at the upper level of
* the XPath.
*
* @return true if this location path is at the top level of the
* expression.
*/
public boolean getIsTopLevel()
{
return m_isTopLevel;
}
/**
* Initialize the context values for this expression
* after it is cloned.
*
* @param execContext The XPath runtime context for this
* transformation.
*/
public void setRoot(int context, Object environment)
{
m_context = context;
XPathContext xctxt = (XPathContext)environment;
m_execContext = xctxt;
m_cdtm = xctxt.getDTM(context);
m_currentContextNode = context;
m_prefixResolver = xctxt.getNamespaceContext();
// m_lastFetched = DTM.NULL;
// m_currentContextNode = DTM.NULL;
// m_foundLast = false;
// m_last = 0;
// m_next = 0;
if (m_isTopLevel)
this.m_stackFrame = xctxt.getVarStack().getStackFrame();
reset();
}
/**
* Set the next position index of this iterator.
*
* @param next A value greater than or equal to zero that indicates the next
* node position to fetch.
*/
protected void setNextPosition(int next)
{
m_next = next;
}
/**
* Get the current position, which is one less than
* the next nextNode() call will retrieve. i.e. if
* you call getCurrentPos() and the return is 0, the next
* fetch will take place at index 1.
*
* @return A value greater than or equal to zero that indicates the next
* node position to fetch.
*/
public final int getCurrentPos()
{
return m_next;
}
/**
* Add one to the current node index.
*/
void incrementNextPosition()
{
m_next++;
}
/**
* If setShouldCacheNodes(true) is called, then nodes will
* be cached. They are not cached by default.
*
* @param b True if this iterator should cache nodes.
*/
public void setShouldCacheNodes(boolean b)
{
if (b)
{
if(null == m_cachedNodes)
{
m_cachedNodes = new NodeSetDTM(getDTMManager());
}
}
else
m_cachedNodes = null;
}
/**
* Tells if this iterator can have nodes added to it or set via
* the <code>setItem(int node, int index)</code> method.
*
* @return True if the nodelist can be mutated.
*/
public boolean isMutable()
{
return (m_cachedNodes != null);
}
/**
* Get cached nodes.
*
* @return Cached nodes.
*/
public NodeSetDTM getCachedNodes()
{
return m_cachedNodes;
}
/**
* Set the current position in the node set.
*
* @param i Must be a valid index greater
* than or equal to zero and less than m_cachedNodes.size().
*/
public void setCurrentPos(int i)
{
// System.out.println("setCurrentPos: "+i);
if (null == m_cachedNodes)
throw new RuntimeException(
"This NodeSetDTM can not do indexing or counting functions!");
setNextPosition(i);
m_cachedNodes.setCurrentPos(i);
// throw new RuntimeException("Who's resetting this thing?");
}
/**
* Get the length of the cached nodes.
*
* <p>Note: for the moment at least, this only returns
* the size of the nodes that have been fetched to date,
* it doesn't attempt to run to the end to make sure we
* have found everything. This should be reviewed.</p>
*
* @return The size of the current cache list.
*/
public int size()
{
if (null == m_cachedNodes)
return 0;
return m_cachedNodes.size();
}
/**
* Returns the <code>index</code> th item in the collection. If
* <code>index</code> is greater than or equal to the number of nodes in
* the list, this returns <code>null</code> .
* @param index Index into the collection.
* @return The node at the <code>index</code> th position in the
* <code>NodeList</code> , or <code>null</code> if that is not a valid
* index.
*/
public int item(int index)
{
// resetToCachedList();
return m_cachedNodes.item(index);
}
/**
* Sets the node at the specified index of this vector to be the
* specified node. The previous component at that position is discarded.
*
* <p>The index must be a value greater than or equal to 0 and less
* than the current size of the vector.
* The iterator must be in cached mode.</p>
*
* <p>Meant to be used for sorted iterators.</p>
*
* @param node Node to set
* @param index Index of where to set the node
*/
public void setItem(int node, int index)
{
m_cachedNodes.setElementAt(node, index);
}
/**
* The number of nodes in the list. The range of valid child node indices
* is 0 to <code>length-1</code> inclusive.
*
* @return The number of nodes in the list, always greater or equal to zero.
*/
public int getLength()
{
// resetToCachedList();
if(m_last > 0)
return m_last;
else if(null == m_cachedNodes || !m_foundLast)
{
m_last = findLastPos(m_execContext);
}
else
{
m_last = m_cachedNodes.getLength();
}
return m_last;
}
/**
* In order to implement NodeList (for extensions), try to reset
* to a cached list for random access.
*/
private void resetToCachedList()
{
// %REVIEW% ? This doesn't seem to work so well...
int pos = this.getCurrentPos();
if ((null == m_cachedNodes) || (pos != 0))
this.setShouldCacheNodes(true);
runTo(-1);
this.setCurrentPos(pos);
}
/**
* Tells if this NodeSetDTM is "fresh", in other words, if
* the first nextNode() that is called will return the
* first node in the set.
*
* @return true of nextNode has not been called.
*/
public boolean isFresh()
{
return (m_next == 0);
}
/**
* Returns the previous node in the set and moves the position of the
* iterator backwards in the set.
* @return The previous <code>Node</code> in the set being iterated over,
* or<code>null</code> if there are no more members in that set.
*/
public int previousNode()
{
if (null == m_cachedNodes)
throw new RuntimeException(
"This NodeSetDTM can not iterate to a previous node!");
return m_cachedNodes.previousNode();
}
/**
* This attribute determines which node types are presented via the
* iterator. The available set of constants is defined in the
* <code>NodeFilter</code> interface.
*
* <p>This is somewhat useless at this time, since it doesn't
* really return information that tells what this iterator will
* show. It is here only to fullfill the DOM NodeIterator
* interface.</p>
*
* @return For now, always NodeFilter.SHOW_ALL & ~NodeFilter.SHOW_ENTITY_REFERENCE.
* @see org.w3c.dom.traversal.NodeIterator
*/
public int getWhatToShow()
{
// TODO: ??
return DTMFilter.SHOW_ALL & ~DTMFilter.SHOW_ENTITY_REFERENCE;
}
/**
* The filter used to screen nodes. Not used at this time,
* this is here only to fullfill the DOM NodeIterator
* interface.
*
* @return Always null.
* @see org.w3c.dom.traversal.NodeIterator
*/
public DTMFilter getFilter()
{
return null;
}
/**
* The root node of the Iterator, as specified when it was created.
*
* @return The "root" of this iterator, which, in XPath terms,
* is the node context for this iterator.
*/
public int getRoot()
{
return m_context;
}
/**
* The value of this flag determines whether the children of entity
* reference nodes are visible to the iterator. If false, they will be
* skipped over.
* <br> To produce a view of the document that has entity references
* expanded and does not expose the entity reference node itself, use the
* whatToShow flags to hide the entity reference node and set
* expandEntityReferences to true when creating the iterator. To produce
* a view of the document that has entity reference nodes but no entity
* expansion, use the whatToShow flags to show the entity reference node
* and set expandEntityReferences to false.
*
* @return Always true, since entity reference nodes are not
* visible in the XPath model.
*/
public boolean getExpandEntityReferences()
{
return true;
}
/** Control over whether it is OK for detach to reset the iterator. */
private boolean m_allowDetach = true;
/**
* Specify if it's OK for detach to release the iterator for reuse.
*
* @param allowRelease true if it is OK for detach to release this iterator
* for pooling.
*/
public void allowDetachToRelease(boolean allowRelease)
{
m_allowDetach = allowRelease;
}
/**
* Detaches the iterator from the set which it iterated over, releasing
* any computational resources and placing the iterator in the INVALID
* state. After<code>detach</code> has been invoked, calls to
* <code>nextNode</code> or<code>previousNode</code> will raise the
* exception INVALID_STATE_ERR.
*/
public void detach()
{
if(m_allowDetach)
{
m_cachedNodes = null;
m_execContext = null;
m_prefixResolver = null;
m_cdtm = null;
m_clones.freeInstance(this);
}
}
/**
* Reset the iterator.
*/
public void reset()
{
// super.reset();
m_foundLast = false;
m_lastFetched = DTM.NULL;
m_next = 0;
m_last = 0;
}
/**
* Get a cloned Iterator that is reset to the beginning
* of the query.
*
* @return A cloned NodeIterator set of the start of the query.
*
* @throws CloneNotSupportedException
*/
public DTMIterator cloneWithReset() throws CloneNotSupportedException
{
LocPathIterator clone = (LocPathIterator) clone();
clone.reset();
return clone;
}
// /**
// * Get a cloned LocPathIterator that holds the same
// * position as this iterator.
// *
// * @return A clone of this iterator that holds the same node position.
// *
// * @throws CloneNotSupportedException
// */
// public Object clone() throws CloneNotSupportedException
// {
//
// LocPathIterator clone = (LocPathIterator) super.clone();
//
// return clone;
// }
/**
* Returns the next node in the set and advances the position of the
* iterator in the set. After a NodeIterator is created, the first call
* to nextNode() returns the first node in the set.
* @return The next <code>Node</code> in the set being iterated over, or
* <code>null</code> if there are no more members in that set.
*/
public abstract int nextNode();
/**
* Bottleneck the return of a next node, to make returns
* easier from nextNode().
*
* @param nextNode The next node found, may be null.
*
* @return The same node that was passed as an argument.
*/
protected int returnNextNode(int nextNode)
{
if (DTM.NULL != nextNode)
{
if (null != m_cachedNodes)
m_cachedNodes.addElement(nextNode);
this.incrementNextPosition();
}
m_lastFetched = nextNode;
if (DTM.NULL == nextNode)
m_foundLast = true;
return nextNode;
}
/**
* Return the last fetched node. Needed to support the UnionPathIterator.
*
* @return The last fetched node, or null if the last fetch was null.
*/
public int getCurrentNode()
{
return m_lastFetched;
}
/**
* If an index is requested, NodeSetDTM will call this method
* to run the iterator to the index. By default this sets
* m_next to the index. If the index argument is -1, this
* signals that the iterator should be run to the end.
*
* @param index The index to run to, or -1 if the iterator
* should run to the end.
*/
public void runTo(int index)
{
if (m_foundLast || ((index >= 0) && (index <= getCurrentPos())))
return;
int n;
if (-1 == index)
{
while (DTM.NULL != (n = nextNode()));
}
else
{
while (DTM.NULL != (n = nextNode()))
{
if (getCurrentPos() >= index)
break;
}
}
}
/**
* Tells if we've found the last node yet.
*
* @return true if the last nextNode returned null.
*/
public final boolean getFoundLast()
{
return m_foundLast;
}
/**
* The XPath execution context we are operating on.
*
* @return XPath execution context this iterator is operating on,
* or null if setRoot has not been called.
*/
public final XPathContext getXPathContext()
{
return m_execContext;
}
/**
* The node context for the iterator.
*
* @return The node context, same as getRoot().
*/
public final int getContext()
{
return m_context;
}
/**
* The node context from where the expression is being
* executed from (i.e. for current() support).
*
* @return The top-level node context of the entire expression.
*/
public final int getCurrentContextNode()
{
return m_currentContextNode;
}
/**
* Set the current context node for this iterator.
*
* @param n Must be a non-null reference to the node context.
*/
public final void setCurrentContextNode(int n)
{
m_currentContextNode = n;
}
// /**
// * Set the current context node for this iterator.
// *
// * @param n Must be a non-null reference to the node context.
// */
// public void setRoot(int n)
// {
// m_context = n;
// m_cdtm = m_execContext.getDTM(n);
// }
/**
* Return the saved reference to the prefix resolver that
* was in effect when this iterator was created.
*
* @return The prefix resolver or this iterator, which may be null.
*/
public final PrefixResolver getPrefixResolver()
{
return m_prefixResolver;
}
/**
* Get the index of the last node in the iteration.
*
*
* @return the index of the last node in the iteration.
*/
public int getLast()
{
return getLength();
}
/**
* Set the index of the last node in the iteration.
*
*
* @param last the index of the last node in the iteration.
*/
public void setLast(int last)
{
m_last = last;
}
/**
* Get the index of the last node that can be itterated to.
* This probably will need to be overridded by derived classes.
*
* @param xctxt XPath runtime context.
*
* @return the index of the last node that can be itterated to.
*/
public int getLastPos(XPathContext xctxt)
{
return getLength();
}
/**
* Get the index of the last node that can be itterated to.
* This probably will need to be overridded by derived classes.
*
* @param xctxt XPath runtime context.
*
* @return the index of the last node that can be itterated to.
*/
public int findLastPos(XPathContext xctxt)
{
int savedPos;
if(null != m_cachedNodes)
savedPos = m_cachedNodes.getCurrentPos();
else
savedPos = -1;
int pos = (m_predicateIndex >= 0) ? getProximityPosition() :
((null != m_cachedNodes) ? m_cachedNodes.getCurrentPos() : m_next);
LocPathIterator clone;
try
{
// %REVIEW% %OPT%
if(0 == pos && m_currentContextNode != DTM.NULL)
clone = (LocPathIterator) cloneWithReset();
else
clone = (LocPathIterator) clone();
}
catch (CloneNotSupportedException cnse)
{
return -1;
}
// We want to clip off the last predicate, but only if we are a sub
// context node list, NOT if we are a context list. See pos68 test,
// also test against bug4638.
int predCount = clone.getPredicateCount();
if(predCount > 0 && this == m_execContext.getSubContextList())
{
// Don't call setPredicateCount, because it clones and is slower.
clone.m_predCount = predCount - 1;
}
int next;
while (DTM.NULL != (next = clone.nextNode()))
{
pos++;
}
if(-1 != savedPos)
m_cachedNodes.setCurrentPos(savedPos);
return pos;
}
// /**
// * Get the analysis pattern built by the WalkerFactory.
// *
// * @return The analysis pattern built by the WalkerFactory.
// */
// int getAnalysis()
// {
// return m_analysis;
// }
// /**
// * Set the analysis pattern built by the WalkerFactory.
// *
// * @param a The analysis pattern built by the WalkerFactory.
// */
// void setAnalysis(int a)
// {
// m_analysis = a;
// }
//============= State Data =============
/**
* The pool for cloned iterators. Iterators need to be cloned
* because the hold running state, and thus the original iterator
* expression from the stylesheet pool can not be used.
*/
transient protected IteratorPool m_clones = new IteratorPool(this);
/**
* The dtm of the context node. Careful about using this... it may not
* be the dtm of the current node.
*/
transient protected DTM m_cdtm;
/**
* The stack frame index for this iterator.
*/
transient int m_stackFrame = -1;
/**
* Value determined at compile time, indicates that this is an
* iterator at the top level of the expression, rather than inside
* a predicate.
* @serial
*/
private boolean m_isTopLevel = false;
/** The index of the last node in the iteration. */
transient protected int m_last = 0;
/** The last node that was fetched, usually by nextNode. */
transient public int m_lastFetched = DTM.NULL;
/**
* If this iterator needs to cache nodes that are fetched, they
* are stored here.
*/
transient NodeSetDTM m_cachedNodes;
/**
* The context node for this iterator, which doesn't change through
* the course of the iteration.
*/
transient protected int m_context = DTM.NULL;
/**
* The node context from where the expression is being
* executed from (i.e. for current() support). Different
* from m_context in that this is the context for the entire
* expression, rather than the context for the subexpression.
*/
transient protected int m_currentContextNode = DTM.NULL;
/**
* Fast access to the current prefix resolver. It isn't really
* clear that this is needed.
* @serial
*/
protected PrefixResolver m_prefixResolver;
/**
* The XPathContext reference, needed for execution of many
* operations.
*/
transient protected XPathContext m_execContext;
/**
* The index of the next node to be fetched. Useful if this
* is a cached iterator, and is being used as random access
* NodeList.
*/
transient protected int m_next;
/**
* Returns true if all the nodes in the iteration well be returned in document
* order.
*
* @return true as a default.
*/
public boolean isDocOrdered()
{
return true;
}
/**
* Returns the axis being iterated, if it is known.
*
* @return Axis.CHILD, etc., or -1 if the axis is not known or is of multiple
* types.
*/
public int getAxis()
{
return -1;
}
// /**
// * The analysis pattern built by the WalkerFactory.
// * TODO: Move to LocPathIterator.
// * @see org.apache.xpath.axes.WalkerFactory
// * @serial
// */
// protected int m_analysis = 0x00000000;
}