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	/*
	* Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
	*/
	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You under the Apache License, Version 2.0
	* (the "License"); you may not use this file except in compliance with
	* the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.sun.org.apache.xerces.internal.impl.xs.identity;

	import com.sun.org.apache.xerces.internal.impl.Constants;
	import com.sun.org.apache.xerces.internal.impl.xpath.XPath;
	import com.sun.org.apache.xerces.internal.util.IntStack;
	import com.sun.org.apache.xerces.internal.xni.QName;
	import com.sun.org.apache.xerces.internal.xni.XMLAttributes;
	import com.sun.org.apache.xerces.internal.xs.AttributePSVI;
	import com.sun.org.apache.xerces.internal.xs.ShortList;
	import com.sun.org.apache.xerces.internal.xs.XSTypeDefinition;
	import org.xml.sax.SAXException;


	/**
	* XPath matcher.
	*
	* @xerces.internal
	*
	* @author Andy Clark, IBM
	*
	*/
	public class XPathMatcher {

	//
	// Constants
	//

	// debugging

	/** Compile to true to debug everything. */
	protected static final boolean DEBUG_ALL = false;

	/** Compile to true to debug method callbacks. */
	protected static final boolean DEBUG_METHODS = false \|\| DEBUG_ALL;

	/** Compile to true to debug important method callbacks. */
	protected static final boolean DEBUG_METHODS2 = false \|\| DEBUG_METHODS \|\| DEBUG_ALL;

	/** Compile to true to debug the <em>really</em> important methods. */
	protected static final boolean DEBUG_METHODS3 = false \|\| DEBUG_METHODS \|\| DEBUG_ALL;

	/** Compile to true to debug match. */
	protected static final boolean DEBUG_MATCH = false \|\| DEBUG_ALL;

	/** Compile to true to debug step index stack. */
	protected static final boolean DEBUG_STACK = false \|\| DEBUG_ALL;

	/** Don't touch this value unless you add more debug constants. */
	protected static final boolean DEBUG_ANY = DEBUG_METHODS \|\|
	DEBUG_METHODS2 \|\|
	DEBUG_METHODS3 \|\|
	DEBUG_MATCH \|\|
	DEBUG_STACK;

	// constants describing whether a match was made,
	// and if so how.
	// matched any way
	protected static final int MATCHED = 1;
	// matched on the attribute axis
	protected static final int MATCHED_ATTRIBUTE = 3;
	// matched on the descendant-or-self axixs
	protected static final int MATCHED_DESCENDANT = 5;
	// matched some previous (ancestor) node on the descendant-or-self-axis, but not this node
	protected static final int MATCHED_DESCENDANT_PREVIOUS = 13;

	//
	// Data
	//

	/** XPath location path. */
	private XPath.LocationPath[] fLocationPaths;

	/** True if XPath has been matched. */
	private int[] fMatched;

	/** The matching string. */
	protected Object fMatchedString;

	/** Integer stack of step indexes. */
	private IntStack[] fStepIndexes;

	/** Current step. */
	private int[] fCurrentStep;

	/**
	* No match depth. The value of this field will be zero while
	* matching is successful for the given xpath expression.
	*/
	private int [] fNoMatchDepth;

	final QName fQName = new QName();


	//
	// Constructors
	//

	/**
	* Constructs an XPath matcher that implements a document fragment
	* handler.
	*
	* @param xpath The xpath.
	*/
	public XPathMatcher(XPath xpath) {
	fLocationPaths = xpath.getLocationPaths();
	fStepIndexes = new IntStack[fLocationPaths.length];
	for(int i=0; i<fStepIndexes.length; i++) fStepIndexes[i] = new IntStack();
	fCurrentStep = new int[fLocationPaths.length];
	fNoMatchDepth = new int[fLocationPaths.length];
	fMatched = new int[fLocationPaths.length];
	} // <init>(XPath)

	//
	// Public methods
	//

	/**
	* Returns value of first member of fMatched that
	* is nonzero.
	*/
	public boolean isMatched() {
	// xpath has been matched if any one of the members of the union have matched.
	for (int i=0; i < fLocationPaths.length; i++)
	if (((fMatched[i] & MATCHED) == MATCHED)
	&& ((fMatched[i] & MATCHED_DESCENDANT_PREVIOUS) != MATCHED_DESCENDANT_PREVIOUS)
	&& ((fNoMatchDepth[i] == 0)
	\|\| ((fMatched[i] & MATCHED_DESCENDANT) == MATCHED_DESCENDANT)))
	return true;

	return false;
	} // isMatched():int

	//
	// Protected methods
	//

	// a place-holder method; to be overridden by subclasses
	// that care about matching element content.
	protected void handleContent(XSTypeDefinition type, boolean nillable,
	Object value, short valueType, ShortList itemValueType) {
	}

	/**
	* This method is called when the XPath handler matches the
	* XPath expression. Subclasses can override this method to
	* provide default handling upon a match.
	*/
	protected void matched(Object actualValue, short valueType,
	ShortList itemValueType, boolean isNil) {
	if (DEBUG_METHODS3) {
	System.out.println(toString()+"#matched(\""+actualValue+"\")");
	}
	} // matched(String content, XSSimpleType val)

	//
	// ~XMLDocumentFragmentHandler methods
	//

	/**
	* The start of the document fragment.
	*/
	public void startDocumentFragment(){
	if (DEBUG_METHODS) {
	System.out.println(toString()+"#startDocumentFragment("+
	")");
	}

	// reset state
	fMatchedString = null;
	for(int i = 0; i < fLocationPaths.length; i++) {
	fStepIndexes[i].clear();
	fCurrentStep[i] = 0;
	fNoMatchDepth[i] = 0;
	fMatched[i] = 0;
	}


	} // startDocumentFragment()

	/**
	* The start of an element. If the document specifies the start element
	* by using an empty tag, then the startElement method will immediately
	* be followed by the endElement method, with no intervening methods.
	*
	* @param element The name of the element.
	* @param attributes The element attributes.
	*
	* @throws SAXException Thrown by handler to signal an error.
	*/
	public void startElement(QName element, XMLAttributes attributes){
	if (DEBUG_METHODS2) {
	System.out.println(toString()+"#startElement("+
	"element={"+element+"},"+
	"attributes=..."+attributes+
	")");
	}

	for(int i = 0; i < fLocationPaths.length; i++) {
	// push context
	int startStep = fCurrentStep[i];
	fStepIndexes[i].push(startStep);

	// try next xpath, if not matching
	if ((fMatched[i] & MATCHED_DESCENDANT) == MATCHED \|\| fNoMatchDepth[i] > 0) {
	fNoMatchDepth[i]++;
	continue;
	}
	if((fMatched[i] & MATCHED_DESCENDANT) == MATCHED_DESCENDANT) {
	fMatched[i] = MATCHED_DESCENDANT_PREVIOUS;
	}

	if (DEBUG_STACK) {
	System.out.println(toString()+": "+fStepIndexes[i]);
	}

	// consume self::node() steps
	XPath.Step[] steps = fLocationPaths[i].steps;
	while (fCurrentStep[i] < steps.length &&
	steps[fCurrentStep[i]].axis.type == XPath.Axis.SELF) {
	if (DEBUG_MATCH) {
	XPath.Step step = steps[fCurrentStep[i]];
	System.out.println(toString()+" [SELF] MATCHED!");
	}
	fCurrentStep[i]++;
	}
	if (fCurrentStep[i] == steps.length) {
	if (DEBUG_MATCH) {
	System.out.println(toString()+" XPath MATCHED!");
	}
	fMatched[i] = MATCHED;
	continue;
	}

	// now if the current step is a descendant step, we let the next
	// step do its thing; if it fails, we reset ourselves
	// to look at this step for next time we're called.
	// so first consume all descendants:
	int descendantStep = fCurrentStep[i];
	while(fCurrentStep[i] < steps.length &&
	steps[fCurrentStep[i]].axis.type == XPath.Axis.DESCENDANT) {
	if (DEBUG_MATCH) {
	XPath.Step step = steps[fCurrentStep[i]];
	System.out.println(toString()+" [DESCENDANT] MATCHED!");
	}
	fCurrentStep[i]++;
	}
	boolean sawDescendant = fCurrentStep[i] > descendantStep;
	if (fCurrentStep[i] == steps.length) {
	if (DEBUG_MATCH) {
	System.out.println(toString()+" XPath DIDN'T MATCH!");
	}
	fNoMatchDepth[i]++;
	if (DEBUG_MATCH) {
	System.out.println(toString()+" [CHILD] after NO MATCH");
	}
	continue;
	}

	// match child::... step, if haven't consumed any self::node()
	if ((fCurrentStep[i] == startStep \|\| fCurrentStep[i] > descendantStep) &&
	steps[fCurrentStep[i]].axis.type == XPath.Axis.CHILD) {
	XPath.Step step = steps[fCurrentStep[i]];
	XPath.NodeTest nodeTest = step.nodeTest;
	if (DEBUG_MATCH) {
	System.out.println(toString()+" [CHILD] before");
	}
	if (nodeTest.type == XPath.NodeTest.QNAME) {
	if (!nodeTest.name.equals(element)) {
	if(fCurrentStep[i] > descendantStep) {
	fCurrentStep[i] = descendantStep;
	continue;
	}
	fNoMatchDepth[i]++;
	if (DEBUG_MATCH) {
	System.out.println(toString()+" [CHILD] after NO MATCH");
	}
	continue;
	}
	}
	fCurrentStep[i]++;
	if (DEBUG_MATCH) {
	System.out.println(toString()+" [CHILD] after MATCHED!");
	}
	}
	if (fCurrentStep[i] == steps.length) {
	if(sawDescendant) {
	fCurrentStep[i] = descendantStep;
	fMatched[i] = MATCHED_DESCENDANT;
	} else {
	fMatched[i] = MATCHED;
	}
	continue;
	}

	// match attribute::... step
	if (fCurrentStep[i] < steps.length &&
	steps[fCurrentStep[i]].axis.type == XPath.Axis.ATTRIBUTE) {
	if (DEBUG_MATCH) {
	System.out.println(toString()+" [ATTRIBUTE] before");
	}
	int attrCount = attributes.getLength();
	if (attrCount > 0) {
	XPath.NodeTest nodeTest = steps[fCurrentStep[i]].nodeTest;

	for (int aIndex = 0; aIndex < attrCount; aIndex++) {
	attributes.getName(aIndex, fQName);
	if (nodeTest.type != XPath.NodeTest.QNAME \|\|
	nodeTest.name.equals(fQName)) {
	fCurrentStep[i]++;
	if (fCurrentStep[i] == steps.length) {
	fMatched[i] = MATCHED_ATTRIBUTE;
	int j=0;
	for(; j<i && ((fMatched[j] & MATCHED) != MATCHED); j++);
	if(j==i) {
	AttributePSVI attrPSVI = (AttributePSVI)attributes.
	getAugmentations(aIndex).getItem(Constants.ATTRIBUTE_PSVI);
	fMatchedString = attrPSVI.getSchemaValue().getActualValue();
	matched(fMatchedString, attrPSVI.getSchemaValue().getActualValueType(),
	attrPSVI.getSchemaValue().getListValueTypes(), false);
	}
	}
	break;
	}
	}
	}
	if ((fMatched[i] & MATCHED) != MATCHED) {
	if(fCurrentStep[i] > descendantStep) {
	fCurrentStep[i] = descendantStep;
	continue;
	}
	fNoMatchDepth[i]++;
	if (DEBUG_MATCH) {
	System.out.println(toString()+" [ATTRIBUTE] after");
	}
	continue;
	}
	if (DEBUG_MATCH) {
	System.out.println(toString()+" [ATTRIBUTE] after MATCHED!");
	}
	}
	}

	}
	// startElement(QName,XMLAttrList,int)

	/**
	* @param element
	* name of the element.
	* @param type
	* content type of this element. IOW, the XML schema type
	* of the <tt>value</tt>. Note that this may not be the type declared
	* in the element declaration, but it is "the actual type". For example,
	* if the XML is <foo xsi:type="xs:string">aaa</foo>, this
	* parameter will be "xs:string".
	* @param nillable - nillable
	* true if the element declaration is nillable.
	* @param value - actual value
	* the typed value of the content of this element.
	*/
	public void endElement(QName element, XSTypeDefinition type, boolean nillable,
	Object value, short valueType, ShortList itemValueType) {
	if (DEBUG_METHODS2) {
	System.out.println(toString()+"#endElement("+
	"element={"+element+"},"+
	")");
	}
	for(int i = 0; i<fLocationPaths.length; i++) {
	// go back a step
	fCurrentStep[i] = fStepIndexes[i].pop();

	// don't do anything, if not matching
	if (fNoMatchDepth[i] > 0) {
	fNoMatchDepth[i]--;
	}

	// signal match, if appropriate
	else {
	int j=0;
	for(; j<i && ((fMatched[j] & MATCHED) != MATCHED); j++);
	if ((j<i) \|\| (fMatched[j] == 0) \|\|
	((fMatched[j] & MATCHED_ATTRIBUTE) == MATCHED_ATTRIBUTE)) {
	continue;
	}
	// only certain kinds of matchers actually
	// match element content. This permits
	// them a way to override this to do nothing
	// and hopefully save a few operations.
	handleContent(type, nillable, value, valueType, itemValueType);
	fMatched[i] = 0;
	}

	if (DEBUG_STACK) {
	System.out.println(toString()+": "+fStepIndexes[i]);
	}
	}

	} // endElement(QName)

	//
	// Object methods
	//

	/** Returns a string representation of this object. */
	public String toString() {
	/***
	return fLocationPath.toString();
	/***/
	StringBuffer str = new StringBuffer();
	String s = super.toString();
	int index2 = s.lastIndexOf('.');
	if (index2 != -1) {
	s = s.substring(index2 + 1);
	}
	str.append(s);
	for(int i =0;i<fLocationPaths.length; i++) {
	str.append('[');
	XPath.Step[] steps = fLocationPaths[i].steps;
	for (int j = 0; j < steps.length; j++) {
	if (j == fCurrentStep[i]) {
	str.append('^');
	}
	str.append(steps[j].toString());
	if (j < steps.length - 1) {
	str.append('/');
	}
	}
	if (fCurrentStep[i] == steps.length) {
	str.append('^');
	}
	str.append(']');
	str.append(',');
	}
	return str.toString();
	} // toString():String

	//
	// Private methods
	//

	/** Normalizes text. */
	private String normalize(String s) {
	StringBuffer str = new StringBuffer();
	int length = s.length();
	for (int i = 0; i < length; i++) {
	char c = s.charAt(i);
	switch (c) {
	case '\n': {
	str.append("\\n");
	break;
	}
	default: {
	str.append(c);
	}
	}
	}
	return str.toString();
	} // normalize(String):String

	//
	// MAIN
	//

	// NOTE: The main of this class is here for debugging purposes.
	// However, javac (JDK 1.1.8) has an internal compiler
	// error when compiling. Jikes has no problem, though.
	//
	// If you want to use this main, use Jikes to compile but
	// never check in this code to CVS without commenting it
	// out. -Ac

	/** Main program. */
	/***
	public static void main(String[] argv) throws XNIException {

	if (DEBUG_ANY) {
	for (int i = 0; i < argv.length; i++) {
	final String expr = argv[i];
	final XPath xpath = new XPath(expr, symbols, null);
	final XPathMatcher matcher = new XPathMatcher(xpath, true);
	com.sun.org.apache.xerces.internal.parsers.SAXParser parser =
	new com.sun.org.apache.xerces.internal.parsers.SAXParser(symbols) {
	public void startDocument() throws XNIException {
	matcher.startDocumentFragment(symbols, null);
	}
	public void startElement(QName element, XMLAttrList attributes, int handle) throws XNIException {
	matcher.startElement(element, attributes, handle);
	}
	public void characters(char[] ch, int offset, int length) throws XNIException {
	matcher.characters(ch, offset, length);
	}
	public void endElement(QName element) throws XNIException {
	matcher.endElement(element);
	}
	public void endDocument() throws XNIException {
	matcher.endDocumentFragment();
	}
	};
	System.out.println("#### argv["+i+"]: \""+expr+"\" -> \""+xpath.toString()+'"');
	final String uri = argv[++i];
	System.out.println("#### argv["+i+"]: "+uri);
	parser.parse(uri);
	}
	}

	} // main(String[])
	/***/

	} // class XPathMatcher

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