content: /*
   *  This file is part of AndroidIDE.
   *
   *  AndroidIDE is free software: you can redistribute it and/or modify
   *  it under the terms of the GNU General Public License as published by
   *  the Free Software Foundation, either version 3 of the License, or
   *  (at your option) any later version.
   *
   *  AndroidIDE is distributed in the hope that it will be useful,
   *  but WITHOUT ANY WARRANTY; without even the implied warranty of
   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *  GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License
   *   along with AndroidIDE.  If not, see <https://www.gnu.org/licenses/>.
   */
  
  /*
   * reserved comment block
   * DO NOT REMOVE OR ALTER!
   */
  /*
   * Copyright 1999-2004 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.
   */
  /*
   * $Id: XStringForFSB.java,v 1.2.4.2 2005/09/14 20:46:27 jeffsuttor Exp $
   */
  package jaxp.sun.org.apache.xpath.internal.objects;
  
  import jaxp.sun.org.apache.xalan.internal.res.XSLMessages;
  import jaxp.sun.org.apache.xml.internal.utils.FastStringBuffer;
  import jaxp.sun.org.apache.xml.internal.utils.XMLCharacterRecognizer;
  import jaxp.sun.org.apache.xml.internal.utils.XMLString;
  import jaxp.sun.org.apache.xml.internal.utils.XMLStringFactory;
  import jaxp.sun.org.apache.xpath.internal.res.XPATHErrorResources;
  import jaxp.xml.transform.TransformerException;
  
  /**
   * This class will wrap a FastStringBuffer and allow for
   */
  public class XStringForFSB extends XString
  {
      static final long serialVersionUID = -1533039186550674548L;
  
    /** The start position in the fsb. */
    int m_start;
  
    /** The length of the string. */
    int m_length;
  
    /** If the str() function is called, the string will be cached here. */
    protected String m_strCache = null;
  
    /** cached hash code */
    protected int m_hash = 0;
  
    /**
     * Construct a XNodeSet object.
     *
     * @param val FastStringBuffer object this will wrap, must be non-null.
     * @param start The start position in the array.
     * @param length The number of characters to read from the array.
     */
    public XStringForFSB(FastStringBuffer val, int start, int length)
    {
  
      super(val);
  
      m_start = start;
      m_length = length;
  
      if (null == val)
        throw new IllegalArgumentException(
          XSLMessages.createXPATHMessage(XPATHErrorResources.ER_FASTSTRINGBUFFER_CANNOT_BE_NULL, null));
    }
  
    /**
     * Construct a XNodeSet object.
     *
     * @param val String object this will wrap.
     */
    private XStringForFSB(String val)
    {
  
      super(val);
  
      throw new IllegalArgumentException(
        XSLMessages.createXPATHMessage(XPATHErrorResources.ER_FSB_CANNOT_TAKE_STRING, null)); // "XStringForFSB can not take a string for an argument!");
    }
  
    /**
     * Cast result object to a string.
     *
     * @return The string this wraps or the empty string if null
     */
    public FastStringBuffer fsb()
    {
      return ((FastStringBuffer) m_obj);
    }
  
    /**
     * Cast result object to a string.
     *
     * @return The string this wraps or the empty string if null
     */
    public void appendToFsb(FastStringBuffer fsb)
    {
      // %OPT% !!! FSB has to be updated to take partial fsb's for append.
      fsb.append(str());
    }
  
    /**
     * Tell if this object contains a java String object.
     *
     * @return true if this XMLString can return a string without creating one.
     */
    public boolean hasString()
    {
      return (null != m_strCache);
    }
  
  //  /** NEEDSDOC Field strCount */
  //  public static int strCount = 0;
  //
  //  /** NEEDSDOC Field xtable */
  //  static java.util.Hashtable xtable = new java.util.Hashtable();
  
    /**
     * Since this object is incomplete without the length and the offset, we
     * have to convert to a string when this function is called.
     *
     * @return The java String representation of this object.
     */
    public Object object()
    {
      return str();
    }
  
    /**
     * Cast result object to a string.
     *
     * @return The string this wraps or the empty string if null
     */
    public String str()
    {
  
      if (null == m_strCache)
      {
        m_strCache = fsb().getString(m_start, m_length);
  
  //      strCount++;
  //
  //      RuntimeException e = new RuntimeException("Bad!  Bad!");
  //      java.io.CharArrayWriter writer = new java.io.CharArrayWriter();
  //      java.io.PrintWriter pw = new java.io.PrintWriter(writer);
  //
  //      e.printStackTrace(pw);
  //
  //      String str = writer.toString();
  //
  //      str = str.substring(0, 600);
  //
  //      if (null == xtable.get(str))
  //      {
  //        xtable.put(str, str);
  //        System.out.println(str);
  //      }
  //      System.out.println("strCount: " + strCount);
  
  //      throw e;
  //      e.printStackTrace();
        // System.exit(-1);
      }
  
      return m_strCache;
    }
  
    /**
     * Directly call the
     * characters method on the passed ContentHandler for the
     * string-value. Multiple calls to the
     * ContentHandler's characters methods may well occur for a single call to
     * this method.
     *
     * @param ch A non-null reference to a ContentHandler.
     *
     * @throws org.xml.sax.SAXException
     */
    public void dispatchCharactersEvents(org.xml.sax.ContentHandler ch)
            throws org.xml.sax.SAXException
    {
      fsb().sendSAXcharacters(ch, m_start, m_length);
    }
  
    /**
     * Directly call the
     * comment method on the passed LexicalHandler for the
     * string-value.
     *
     * @param lh A non-null reference to a LexicalHandler.
     *
     * @throws org.xml.sax.SAXException
     */
    public void dispatchAsComment(org.xml.sax.ext.LexicalHandler lh)
            throws org.xml.sax.SAXException
    {
      fsb().sendSAXComment(lh, m_start, m_length);
    }
  
    /**
     * Returns the length of this string.
     *
     * @return  the length of the sequence of characters represented by this
     *          object.
     */
    public int length()
    {
      return m_length;
    }
  
    /**
     * Returns the character at the specified index. An index ranges
     * from <code>0</code> to <code>length() - 1</code>. The first character
     * of the sequence is at index <code>0</code>, the next at index
     * <code>1</code>, and so on, as for array indexing.
     *
     * @param      index   the index of the character.
     * @return     the character at the specified index of this string.
     *             The first character is at index <code>0</code>.
     * @exception  IndexOutOfBoundsException  if the <code>index</code>
     *             argument is negative or not less than the length of this
     *             string.
     */
    public char charAt(int index)
    {
      return fsb().charAt(m_start + index);
    }
  
    /**
     * Copies characters from this string into the destination character
     * array.
     *
     * @param      srcBegin   index of the first character in the string
     *                        to copy.
     * @param      srcEnd     index after the last character in the string
     *                        to copy.
     * @param      dst        the destination array.
     * @param      dstBegin   the start offset in the destination array.
     * @exception IndexOutOfBoundsException If any of the following
     *            is true:
     *            <ul><li><code>srcBegin</code> is negative.
     *            <li><code>srcBegin</code> is greater than <code>srcEnd</code>
     *            <li><code>srcEnd</code> is greater than the length of this
     *                string
     *            <li><code>dstBegin</code> is negative
     *            <li><code>dstBegin+(srcEnd-srcBegin)</code> is larger than
     *                <code>dst.length</code></ul>
     * @exception NullPointerException if <code>dst</code> is <code>null</code>
     */
    public void getChars(int srcBegin, int srcEnd, char dst[], int dstBegin)
    {
  
      // %OPT% Need to call this on FSB when it is implemented.
      // %UNTESTED% (I don't think anyone calls this yet?)
      int n = srcEnd - srcBegin;
  
      if (n > m_length)
        n = m_length;
  
      if (n > (dst.length - dstBegin))
        n = (dst.length - dstBegin);
  
      int end = srcBegin + m_start + n;
      int d = dstBegin;
      FastStringBuffer fsb = fsb();
  
      for (int i = srcBegin + m_start; i < end; i++)
      {
        dst[d++] = fsb.charAt(i);
      }
    }
  
    /**
     * Compares this string to the specified object.
     * The result is <code>true</code> if and only if the argument is not
     * <code>null</code> and is a <code>String</code> object that represents
     * the same sequence of characters as this object.
     *
     * @param   obj2       the object to compare this <code>String</code>
     *                     against.
     *
     * @return  <code>true</code> if the <code>String </code>are equal;
     *          <code>false</code> otherwise.
     * @see     java.lang.String#compareTo(java.lang.String)
     * @see     java.lang.String#equalsIgnoreCase(java.lang.String)
     */
    public boolean equals(XMLString obj2)
    {
  
      if (this == obj2)
      {
        return true;
      }
  
      int n = m_length;
  
      if (n == obj2.length())
      {
        FastStringBuffer fsb = fsb();
        int i = m_start;
        int j = 0;
  
        while (n-- != 0)
        {
          if (fsb.charAt(i) != obj2.charAt(j))
          {
            return false;
          }
  
          i++;
          j++;
        }
  
        return true;
      }
  
      return false;
    }
  
    /**
     * Tell if two objects are functionally equal.
     *
     * @param obj2 Object to compare this to
     *
     * @return true if the two objects are equal
     *
     * @throws TransformerException
     */
    public boolean equals(XObject obj2)
    {
  
      if (this == obj2)
      {
        return true;
      }
      if(obj2.getType() == CLASS_NUMBER)
          return obj2.equals(this);
  
      String str = obj2.str();
      int n = m_length;
  
      if (n == str.length())
      {
        FastStringBuffer fsb = fsb();
        int i = m_start;
        int j = 0;
  
        while (n-- != 0)
        {
          if (fsb.charAt(i) != str.charAt(j))
          {
            return false;
          }
  
          i++;
          j++;
        }
  
        return true;
      }
  
      return false;
    }
  
    /**
     * Tell if two objects are functionally equal.
     *
     * @param anotherString Object to compare this to
     *
     * @return true if the two objects are equal
     *
     * @throws TransformerException
     */
    public boolean equals(String anotherString)
    {
  
      int n = m_length;
  
      if (n == anotherString.length())
      {
        FastStringBuffer fsb = fsb();
        int i = m_start;
        int j = 0;
  
        while (n-- != 0)
        {
          if (fsb.charAt(i) != anotherString.charAt(j))
          {
            return false;
          }
  
          i++;
          j++;
        }
  
        return true;
      }
  
      return false;
    }
  
    /**
     * Compares this string to the specified object.
     * The result is <code>true</code> if and only if the argument is not
     * <code>null</code> and is a <code>String</code> object that represents
     * the same sequence of characters as this object.
     *
     * @param   obj2       the object to compare this <code>String</code>
     *                     against.
     *
     * @return  <code>true</code> if the <code>String </code>are equal;
     *          <code>false</code> otherwise.
     * @see     java.lang.String#compareTo(java.lang.String)
     * @see     java.lang.String#equalsIgnoreCase(java.lang.String)
     */
    public boolean equals(Object obj2)
    {
  
      if (null == obj2)
        return false;
  
      if(obj2 instanceof XNumber)
          return obj2.equals(this);
  
        // In order to handle the 'all' semantics of
        // nodeset comparisons, we always call the
        // nodeset function.
      else if (obj2 instanceof XNodeSet)
        return obj2.equals(this);
      else if (obj2 instanceof XStringForFSB)
        return equals((XMLString) obj2);
      else
        return equals(obj2.toString());
    }
  
    /**
     * Compares this <code>String</code> to another <code>String</code>,
     * ignoring case considerations.  Two strings are considered equal
     * ignoring case if they are of the same length, and corresponding
     * characters in the two strings are equal ignoring case.
     *
     * @param   anotherString   the <code>String</code> to compare this
     *                          <code>String</code> against.
     * @return  <code>true</code> if the argument is not <code>null</code>
     *          and the <code>String</code>s are equal,
     *          ignoring case; <code>false</code> otherwise.
     * @see     #equals(Object)
     * @see     java.lang.Character#toLowerCase(char)
     * @see java.lang.Character#toUpperCase(char)
     */
    public boolean equalsIgnoreCase(String anotherString)
    {
      return (m_length == anotherString.length())
             ? str().equalsIgnoreCase(anotherString) : false;
    }
  
    /**
     * Compares two strings lexicographically.
     *
     * @param   xstr   the <code>String</code> to be compared.
     *
     * @return  the value <code>0</code> if the argument string is equal to
     *          this string; a value less than <code>0</code> if this string
     *          is lexicographically less than the string argument; and a
     *          value greater than <code>0</code> if this string is
     *          lexicographically greater than the string argument.
     * @exception java.lang.NullPointerException if <code>anotherString</code>
     *          is <code>null</code>.
     */
    public int compareTo(XMLString xstr)
    {
  
      int len1 = m_length;
      int len2 = xstr.length();
      int n = Math.min(len1, len2);
      FastStringBuffer fsb = fsb();
      int i = m_start;
      int j = 0;
  
      while (n-- != 0)
      {
        char c1 = fsb.charAt(i);
        char c2 = xstr.charAt(j);
  
        if (c1 != c2)
        {
          return c1 - c2;
        }
  
        i++;
        j++;
      }
  
      return len1 - len2;
    }
  
    /**
     * Compares two strings lexicographically, ignoring case considerations.
     * This method returns an integer whose sign is that of
     * <code>this.toUpperCase().toLowerCase().compareTo(
     * str.toUpperCase().toLowerCase())</code>.
     * <p>
     * Note that this method does <em>not</em> take locale into account,
     * and will result in an unsatisfactory ordering for certain locales.
     * The java.text package provides <em>collators</em> to allow
     * locale-sensitive ordering.
     *
     * @param   xstr   the <code>String</code> to be compared.
     *
     * @return  a negative integer, zero, or a positive integer as the
     *          the specified String is greater than, equal to, or less
     *          than this String, ignoring case considerations.
     * @see     java.text.Collator#compare(String, String)
     * @since   1.2
     */
    public int compareToIgnoreCase(XMLString xstr)
    {
  
      int len1 = m_length;
      int len2 = xstr.length();
      int n = Math.min(len1, len2);
      FastStringBuffer fsb = fsb();
      int i = m_start;
      int j = 0;
  
      while (n-- != 0)
      {
        char c1 = Character.toLowerCase(fsb.charAt(i));
        char c2 = Character.toLowerCase(xstr.charAt(j));
  
        if (c1 != c2)
        {
          return c1 - c2;
        }
  
        i++;
        j++;
      }
  
      return len1 - len2;
    }
  
    /**
     * Returns a hashcode for this string. The hashcode for a
     * <code>String</code> object is computed as
     * <blockquote><pre>
     * s[0]*31^(n-1) + s[1]*31^(n-2) + ... + s[n-1]
     * </pre></blockquote>
     * using <code>int</code> arithmetic, where <code>s[i]</code> is the
     * <i>i</i>th character of the string, <code>n</code> is the length of
     * the string, and <code>^</code> indicates exponentiation.
     * (The hash value of the empty string is zero.)
     *
     * @return  a hash code value for this object.
     */
    public int hashCode()
    {
      // Commenting this out because in JDK1.1.8 and VJ++
      // we don't match XMLStrings. Defaulting to the super
      // causes us to create a string, but at this point
      // this only seems to get called in key processing.
      // Maybe we can live with it?
  
  /*
      int h = m_hash;
  
      if (h == 0)
      {
        int off = m_start;
        int len = m_length;
        FastStringBuffer fsb = fsb();
  
        for (int i = 0; i < len; i++)
        {
          h = 31 * h + fsb.charAt(off);
  
          off++;
        }
  
        m_hash = h;
      }
      */
  
      return super.hashCode(); // h;
    }
  
    /**
     * Tests if this string starts with the specified prefix beginning
     * a specified index.
     *
     * @param   prefix    the prefix.
     * @param   toffset   where to begin looking in the string.
     * @return  <code>true</code> if the character sequence represented by the
     *          argument is a prefix of the substring of this object starting
     *          at index <code>toffset</code>; <code>false</code> otherwise.
     *          The result is <code>false</code> if <code>toffset</code> is
     *          negative or greater than the length of this
     *          <code>String</code> object; otherwise the result is the same
     *          as the result of the expression
     *          <pre>
     *          this.subString(toffset).startsWith(prefix)
     *          </pre>
     * @exception java.lang.NullPointerException if <code>prefix</code> is
     *          <code>null</code>.
     */
    public boolean startsWith(XMLString prefix, int toffset)
    {
  
      FastStringBuffer fsb = fsb();
      int to = m_start + toffset;
      int tlim = m_start + m_length;
      int po = 0;
      int pc = prefix.length();
  
      // Note: toffset might be near -1>>>1.
      if ((toffset < 0) || (toffset > m_length - pc))
      {
        return false;
      }
  
      while (--pc >= 0)
      {
        if (fsb.charAt(to) != prefix.charAt(po))
        {
          return false;
        }
  
        to++;
        po++;
      }
  
      return true;
    }
  
    /**
     * Tests if this string starts with the specified prefix.
     *
     * @param   prefix   the prefix.
     * @return  <code>true</code> if the character sequence represented by the
     *          argument is a prefix of the character sequence represented by
     *          this string; <code>false</code> otherwise.
     *          Note also that <code>true</code> will be returned if the
     *          argument is an empty string or is equal to this
     *          <code>String</code> object as determined by the
     *          {@link #equals(Object)} method.
     * @exception java.lang.NullPointerException if <code>prefix</code> is
     *          <code>null</code>.
     * @since   JDK1. 0
     */
    public boolean startsWith(XMLString prefix)
    {
      return startsWith(prefix, 0);
    }
  
    /**
     * Returns the index within this string of the first occurrence of the
     * specified character. If a character with value <code>ch</code> occurs
     * in the character sequence represented by this <code>String</code>
     * object, then the index of the first such occurrence is returned --
     * that is, the smallest value <i>k</i> such that:
     * <blockquote><pre>
     * this.charAt(<i>k</i>) == ch
     * </pre></blockquote>
     * is <code>true</code>. If no such character occurs in this string,
     * then <code>-1</code> is returned.
     *
     * @param   ch   a character.
     * @return  the index of the first occurrence of the character in the
     *          character sequence represented by this object, or
     *          <code>-1</code> if the character does not occur.
     */
    public int indexOf(int ch)
    {
      return indexOf(ch, 0);
    }
  
    /**
     * Returns the index within this string of the first occurrence of the
     * specified character, starting the search at the specified index.
     * <p>
     * If a character with value <code>ch</code> occurs in the character
     * sequence represented by this <code>String</code> object at an index
     * no smaller than <code>fromIndex</code>, then the index of the first
     * such occurrence is returned--that is, the smallest value <i>k</i>
     * such that:
     * <blockquote><pre>
     * (this.charAt(<i>k</i>) == ch) && (<i>k</i> >= fromIndex)
     * </pre></blockquote>
     * is true. If no such character occurs in this string at or after
     * position <code>fromIndex</code>, then <code>-1</code> is returned.
     * <p>
     * There is no restriction on the value of <code>fromIndex</code>. If it
     * is negative, it has the same effect as if it were zero: this entire
     * string may be searched. If it is greater than the length of this
     * string, it has the same effect as if it were equal to the length of
     * this string: <code>-1</code> is returned.
     *
     * @param   ch          a character.
     * @param   fromIndex   the index to start the search from.
     * @return  the index of the first occurrence of the character in the
     *          character sequence represented by this object that is greater
     *          than or equal to <code>fromIndex</code>, or <code>-1</code>
     *          if the character does not occur.
     */
    public int indexOf(int ch, int fromIndex)
    {
  
      int max = m_start + m_length;
      FastStringBuffer fsb = fsb();
  
      if (fromIndex < 0)
      {
        fromIndex = 0;
      }
      else if (fromIndex >= m_length)
      {
  
        // Note: fromIndex might be near -1>>>1.
        return -1;
      }
  
      for (int i = m_start + fromIndex; i < max; i++)
      {
        if (fsb.charAt(i) == ch)
        {
          return i - m_start;
        }
      }
  
      return -1;
    }
  
    /**
     * Returns a new string that is a substring of this string. The
     * substring begins with the character at the specified index and
     * extends to the end of this string. <p>
     * Examples:
     * <blockquote><pre>
     * "unhappy".substring(2) returns "happy"
     * "Harbison".substring(3) returns "bison"
     * "emptiness".substring(9) returns "" (an empty string)
     * </pre></blockquote>
     *
     * @param      beginIndex   the beginning index, inclusive.
     * @return     the specified substring.
     * @exception  IndexOutOfBoundsException  if
     *             <code>beginIndex</code> is negative or larger than the
     *             length of this <code>String</code> object.
     */
    public XMLString substring(int beginIndex)
    {
  
      int len = m_length - beginIndex;
  
      if (len <= 0)
        return EMPTYSTRING;
      else
      {
        int start = m_start + beginIndex;
  
        return new XStringForFSB(fsb(), start, len);
      }
    }
  
    /**
     * Returns a new string that is a substring of this string. The
     * substring begins at the specified <code>beginIndex</code> and
     * extends to the character at index <code>endIndex - 1</code>.
     * Thus the length of the substring is <code>endIndex-beginIndex</code>.
     *
     * @param      beginIndex   the beginning index, inclusive.
     * @param      endIndex     the ending index, exclusive.
     * @return     the specified substring.
     * @exception  IndexOutOfBoundsException  if the
     *             <code>beginIndex</code> is negative, or
     *             <code>endIndex</code> is larger than the length of
     *             this <code>String</code> object, or
     *             <code>beginIndex</code> is larger than
     *             <code>endIndex</code>.
     */
    public XMLString substring(int beginIndex, int endIndex)
    {
  
      int len = endIndex - beginIndex;
  
      if (len > m_length)
        len = m_length;
  
      if (len <= 0)
        return EMPTYSTRING;
      else
      {
        int start = m_start + beginIndex;
  
        return new XStringForFSB(fsb(), start, len);
      }
    }
  
    /**
     * Concatenates the specified string to the end of this string.
     *
     * @param   str   the <code>String</code> that is concatenated to the end
     *                of this <code>String</code>.
     * @return  a string that represents the concatenation of this object's
     *          characters followed by the string argument's characters.
     * @exception java.lang.NullPointerException if <code>str</code> is
     *          <code>null</code>.
     */
    public XMLString concat(String str)
    {
  
      // %OPT% Make an FSB here?
      return new XString(str().concat(str));
    }
  
    /**
     * Removes white space from both ends of this string.
     *
     * @return  this string, with white space removed from the front and end.
     */
    public XMLString trim()
    {
      return fixWhiteSpace(true, true, false);
    }
  
    /**
     * Returns whether the specified <var>ch</var> conforms to the XML 1.0 definition
     * of whitespace.  Refer to <A href="http://www.w3.org/TR/1998/REC-xml-19980210#NT-S">
     * the definition of <CODE>S</CODE></A> for details.
     * @param   ch      Character to check as XML whitespace.
     * @return          =true if <var>ch</var> is XML whitespace; otherwise =false.
     */
    private static boolean isSpace(char ch)
    {
      return XMLCharacterRecognizer.isWhiteSpace(ch);  // Take the easy way out for now.
    }
  
    /**
     * Conditionally trim all leading and trailing whitespace in the specified String.
     * All strings of white space are
     * replaced by a single space character (#x20), except spaces after punctuation which
     * receive double spaces if doublePunctuationSpaces is true.
     * This function may be useful to a formatter, but to get first class
     * results, the formatter should probably do it's own white space handling
     * based on the semantics of the formatting object.
     *
     * @param   trimHead    Trim leading whitespace?
     * @param   trimTail    Trim trailing whitespace?
     * @param   doublePunctuationSpaces    Use double spaces for punctuation?
     * @return              The trimmed string.
     */
    public XMLString fixWhiteSpace(boolean trimHead, boolean trimTail,
                                   boolean doublePunctuationSpaces)
    {
  
      int end = m_length + m_start;
      char[] buf = new char[m_length];
      FastStringBuffer fsb = fsb();
      boolean edit = false;
  
      /* replace S to ' '. and ' '+ -> single ' '. */
      int d = 0;
      boolean pres = false;
  
      for (int s = m_start; s < end; s++)
      {
        char c = fsb.charAt(s);
  
        if (isSpace(c))
        {
          if (!pres)
          {
            if (' ' != c)
            {
              edit = true;
            }
  
            buf[d++] = ' ';
  
            if (doublePunctuationSpaces && (d != 0))
            {
              char prevChar = buf[d - 1];
  
              if (!((prevChar == '.') || (prevChar == '!')
                    || (prevChar == '?')))
              {
                pres = true;
              }
            }
            else
            {
              pres = true;
            }
          }
          else
          {
            edit = true;
            pres = true;
          }
        }
        else
        {
          buf[d++] = c;
          pres = false;
        }
      }
  
      if (trimTail && 1 <= d && ' ' == buf[d - 1])
      {
        edit = true;
  
        d--;
      }
  
      int start = 0;
  
      if (trimHead && 0 < d && ' ' == buf[0])
      {
        edit = true;
  
        start++;
      }
  
      XMLStringFactory xsf = XMLStringFactoryImpl.getFactory();
  
      return edit ? xsf.newstr(buf, start, d - start) : this;
    }
  
    /**
     * Convert a string to a double -- Allowed input is in fixed
     * notation ddd.fff.
     *
     * %OPT% CHECK PERFORMANCE against generating a Java String and
     * converting it to double. The advantage of running in native
     * machine code -- perhaps even microcode, on some systems -- may
     * more than make up for the cost of allocating and discarding the
     * additional object. We need to benchmark this.
     *
     * %OPT% More importantly, we need to decide whether we _care_ about
     * the performance of this operation. Does XString.toDouble constitute
     * any measurable percentage of our typical runtime? I suspect not!
     *
     * @return A double value representation of the string, or return Double.NaN
     * if the string can not be converted.  */
    public double toDouble()
    {
      if(m_length == 0)
        return Double.NaN;
      int i;
      char c;
      String valueString = fsb().getString(m_start,m_length);
  
      // The following are permitted in the Double.valueOf, but not by the XPath spec:
      // - a plus sign
      // - The use of e or E to indicate exponents
      // - trailing f, F, d, or D
      // See function comments; not sure if this is slower than actually doing the
      // conversion ourselves (as was before).
  
      for (i=0;i<m_length;i++)
        if (!XMLCharacterRecognizer.isWhiteSpace(valueString.charAt(i)))
          break;
      if (i == m_length) return Double.NaN;
      if (valueString.charAt(i) == '-')
        i++;
      for (;i<m_length;i++) {
        c = valueString.charAt(i);
        if (c != '.' && (c < '0' || c > '9'))
          break;
      }
      for (;i<m_length;i++)
        if (!XMLCharacterRecognizer.isWhiteSpace(valueString.charAt(i)))
          break;
      if (i != m_length)
        return Double.NaN;
  
      try {
        return Double.parseDouble(valueString);
      } catch (NumberFormatException nfe) {
        // This should catch double periods, empty strings.
        return Double.NaN;
      }
    }
  }
  