content: /*
   * 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 mf.org.apache.xerces.impl.xs.identity;
  
  import org.xml.sax.SAXException;
  
  import mf.org.apache.xerces.impl.Constants;
  import mf.org.apache.xerces.impl.xpath.XPath;
  import mf.org.apache.xerces.util.IntStack;
  import mf.org.apache.xerces.xni.QName;
  import mf.org.apache.xerces.xni.XMLAttributes;
  import mf.org.apache.xerces.xs.AttributePSVI;
  import mf.org.apache.xerces.xs.ShortList;
  import mf.org.apache.xerces.xs.XSTypeDefinition;
  
  /**
   * XPath matcher.
   *
   * @author Andy Clark, IBM
   * @version $Id: XPathMatcher.java 572110 2007-09-02 19:04:44Z mrglavas $
   * @xerces.internal
   */
  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
      //
      final QName fQName = new QName();
      /**
       * XPath location path.
       */
      private final XPath.LocationPath[] fLocationPaths;
      /**
       * True if XPath has been matched.
       */
      private final int[] fMatched;
      /**
       * Integer stack of step indexes.
       */
      private final IntStack[] fStepIndexes;
  
      /**
       * Current step.
       */
      private final int[] fCurrentStep;
  
      /**
       * No match depth. The value of this field will be zero while
       * matching is successful for the given xpath expression.
       */
      private final int[] fNoMatchDepth;
      /**
       * The matching string.
       */
      protected Object fMatchedString;
  
  
      //
      // 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 true if the given QName matches the node test.
       **/
      private static boolean matches(XPath.NodeTest nodeTest, QName value) {
          if (nodeTest.type == XPath.NodeTest.QNAME) {
              return nodeTest.name.equals(value);
          }
          if (nodeTest.type == XPath.NodeTest.NAMESPACE) {
              return nodeTest.name.uri == value.uri;
          }
          // XPath.NodeTest.WILDCARD
          return true;
      } // matches(XPath.NodeTest,QName):boolean
  
      //
      // Protected 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
  
      // 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) {
      }
  
      //
      // ~XMLDocumentFragmentHandler methods
      //
  
      /**
       * 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)
  
      /**
       * 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()
      // startElement(QName,XMLAttrList,int)
  
      /**
       * 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 (!matches(nodeTest, 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 (matches(nodeTest, 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!");
                  }
              }
          }
  
      }
  
      //
      // Object methods
      //
  
      /**
       * @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 &lt;foo xsi:type="xs:string">aaa&lt;/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)) {
                      continue;
                  }
                  if ((fMatched[j] & MATCHED_ATTRIBUTE) == MATCHED_ATTRIBUTE) {
                      fMatched[i] = 0;
                      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)
  
      //
      // Private methods
      //
  
      /**
       * Returns a string representation of this object.
       */
      @Override
      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
  
      /**
       * 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);
       org.apache.xerces.parsers.SAXParser parser =
       new org.apache.xerces.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
  