/*
* Copyright 2001, 2002,2004,2005 The Apache Software Foundation.
*
* Licensed 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
*
* @version $Id: XPathMatcher.java,v 1.2.6.1 2005/09/08 09:02:30 sunithareddy Exp $
*/
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.getActualNormalizedValue();
matched(fMatchedString, attrPSVI.getActualNormalizedValueType(), attrPSVI.getItemValueTypes(), 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