http://xml.apache.org/xalan-j/: Serializer to write out XML, HTML etc. as a stream of characters from an input DOM or from input SAX events. (The Apache Software Foundation) 
/*
 * 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.
 */
/*
 * $Id: XStringForFSB.java 468655 2006-10-28 07:12:06Z minchau $
 */
package org.apache.xpath.objects;

import org.apache.xalan.res.XSLMessages;
import org.apache.xml.utils.FastStringBuffer;
import org.apache.xml.utils.XMLCharacterRecognizer;
import org.apache.xml.utils.XMLString;
import org.apache.xml.utils.XMLStringFactory;
import org.apache.xpath.res.XPATHErrorResources;


This class will wrap a FastStringBuffer and allow for

/**
 * 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. 
/** The start position in the fsb. */
  int m_start;

  
The length of the string. 
/** The length of the string. */
  int m_length;

  
If the str() function is called, the string will be cached here. 
/** If the str() function is called, the string will be cached here. */
  protected String m_strCache = null;

  
cached hash code 
/** cached hash code */
  protected int m_hash = 0;

  
Construct a XNodeSet object.

Params:
  • val – FastStringBuffer object this will wrap, must be non-null.
  • start – The start position in the array.
  • length – The number of characters to read from the array.
/**
   * 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.

Params:
  • val – String object this will wrap.
/**
   * 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.

Returns:The string this wraps or the empty string if null
/**
   * 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.

Returns:The string this wraps or the empty string if null
/**
   * Cast result object to a string.
   *
   * @return The string this wraps or the empty string if null
   */
  public void appendToFsb(org.apache.xml.utils.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.

Returns:true if this XMLString can return a string without creating one.
/**
   * 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.

Returns:The java String representation of this object.
/**
   * 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.

Returns:The string this wraps or the empty string if null
/**
   * 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.

Params:
  • ch – A non-null reference to a ContentHandler.
Throws:
/**
   * 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.

Params:
  • lh – A non-null reference to a LexicalHandler.
Throws:
/**
   * 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.

Returns: the length of the sequence of characters represented by this
         object.
/**
   * 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 0 to length() - 1. The first character
of the sequence is at index 0, the next at index
1, and so on, as for array indexing.

Params:
  • index –   the index of the character.
Throws:
Returns:    the character at the specified index of this string.
            The first character is at index 0.
/**
   * 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.

Params:
  • srcBegin –   index of the first character in the string
                       to copy.
  • srcEnd –     index after the last character in the string
                       to copy.
  • dst –        the destination array.
  • dstBegin –   the start offset in the destination array.
Throws:
  • IndexOutOfBoundsException – If any of the following
           is true:
           
    • srcBegin is negative.
           
    • srcBegin is greater than srcEnd
           
    • srcEnd is greater than the length of this
               string
           
    • dstBegin is negative
           
    • dstBegin+(srcEnd-srcBegin) is larger than
               dst.length
  • NullPointerException – if dst is null
/**
   * 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 true if and only if the argument is not
null and is a String object that represents
the same sequence of characters as this object.

Params:
  • obj2 –       the object to compare this String
                    against.
See Also:
Returns: true if the String are equal;
         false otherwise.
/**
   * 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.

Params:
  • obj2 – Object to compare this to
Throws:
Returns:true if the two objects are equal
/**
   * Tell if two objects are functionally equal.
   *
   * @param obj2 Object to compare this to
   *
   * @return true if the two objects are equal
   *
   * @throws javax.xml.transform.TransformerException
   */
  public boolean equals(XObject obj2)
  {

    if (this == obj2)
    {
      return true;
    }
    if(obj2.getType() == XObject.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.

Params:
  • anotherString – Object to compare this to
Throws:
Returns:true if the two objects are equal
/**
   * Tell if two objects are functionally equal.
   *
   * @param anotherString Object to compare this to
   *
   * @return true if the two objects are equal
   *
   * @throws javax.xml.transform.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 true if and only if the argument is not
null and is a String object that represents
the same sequence of characters as this object.

Params:
  • obj2 –       the object to compare this String
                    against.
See Also:
Returns: true if the String are equal;
         false otherwise.
/**
   * 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 String to another String,
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.

Params:
  • anotherString –   the String to compare this
                         String against.
See Also:
Returns: true if the argument is not null
         and the Strings are equal,
         ignoring case; false otherwise.
/**
   * 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.

Params:
  • xstr –   the String to be compared.
Throws:
Returns: the value 0 if the argument string is equal to
         this string; a value less than 0 if this string
         is lexicographically less than the string argument; and a
         value greater than 0 if this string is
         lexicographically greater than the string argument.
/**
   * 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
this.toUpperCase().toLowerCase().compareTo(
str.toUpperCase().toLowerCase()).


Note that this method does not take locale into account,
and will result in an unsatisfactory ordering for certain locales.
The java.text package provides collators to allow
locale-sensitive ordering.

Params:
  • xstr –   the String to be compared.
See Also:
Returns: 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.
Since:  1.2
/**
   * 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
String object is computed as

s[0]*31^(n-1) + s[1]*31^(n-2) + ... + s[n-1]


using int arithmetic, where s[i] is the
ith character of the string, n is the length of
the string, and ^ indicates exponentiation.
(The hash value of the empty string is zero.)

Returns: a hash code value for this object.
/**
   * 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.

Params:
  • prefix –    the prefix.
  • toffset –   where to begin looking in the string.
Throws:
Returns: true if the character sequence represented by the
         argument is a prefix of the substring of this object starting
         at index toffset; false otherwise.
         The result is false if toffset is
         negative or greater than the length of this
         String object; otherwise the result is the same
         as the result of the expression
         
         this.subString(toffset).startsWith(prefix)
         
/**
   * 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.

Params:
  • prefix –   the prefix.
Throws:
Returns: true if the character sequence represented by the
         argument is a prefix of the character sequence represented by
         this string; false otherwise.
         Note also that true will be returned if the
         argument is an empty string or is equal to this
         String object as determined by the equals(Object) method.
Since:  JDK1. 0
/**
   * 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 ch occurs
in the character sequence represented by this String
object, then the index of the first such occurrence is returned --
that is, the smallest value k such that:

this.charAt(k) == ch


is true. If no such character occurs in this string,
then -1 is returned.

Params:
  • ch –   a character.
Returns: the index of the first occurrence of the character in the
         character sequence represented by this object, or
         -1 if the character does not occur.
/**
   * 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.


If a character with value ch occurs in the character
sequence represented by this String object at an index
no smaller than fromIndex, then the index of the first
such occurrence is returned--that is, the smallest value k
such that:

(this.charAt(k) == ch) && (k >= fromIndex)


is true. If no such character occurs in this string at or after
position fromIndex, then -1 is returned.


There is no restriction on the value of fromIndex. 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: -1 is returned.

Params:
  • ch –          a character.
  • fromIndex –   the index to start the search from.
Returns: the index of the first occurrence of the character in the
         character sequence represented by this object that is greater
         than or equal to fromIndex, or -1
         if the character does not occur.
/**
   * 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. 

Examples:

"unhappy".substring(2) returns "happy"
"Harbison".substring(3) returns "bison"
"emptiness".substring(9) returns "" (an empty string)



Params:
  • beginIndex –   the beginning index, inclusive.
Throws:
Returns:    the specified substring.
/**
   * 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 XString.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 beginIndex and
extends to the character at index endIndex - 1.
Thus the length of the substring is endIndex-beginIndex.

Params:
  • beginIndex –   the beginning index, inclusive.
  • endIndex –     the ending index, exclusive.
Throws:
  • IndexOutOfBoundsException –  if the
            beginIndex is negative, or
            endIndex is larger than the length of
            this String object, or
            beginIndex is larger than
            endIndex.
Returns:    the specified substring.
/**
   * 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 XString.EMPTYSTRING;
    else
    {
      int start = m_start + beginIndex;

      return new XStringForFSB(fsb(), start, len);
    }
  }

  
Concatenates the specified string to the end of this string.

Params:
  • str –   the String that is concatenated to the end
               of this String.
Throws:
Returns: a string that represents the concatenation of this object's
         characters followed by the string argument's characters.
/**
   * 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.

Returns: this string, with white space removed from the front and end.
/**
   * 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 ch conforms to the XML 1.0 definition
of whitespace.  Refer to 
the definition of S for details.

Params:
  • ch –      Character to check as XML whitespace.
Returns:         =true if ch is XML whitespace; otherwise =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.

Params:
  • trimHead –    Trim leading whitespace?
  • trimTail –    Trim trailing whitespace?
  • doublePunctuationSpaces –    Use double spaces for punctuation?
Returns:             The trimmed string.
/**
   * 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!

Returns:A double value representation of the string, or return Double.NaN 
if the string can not be converted.
/**
   * 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 new Double(valueString).doubleValue();
    } catch (NumberFormatException nfe) {
      // This should catch double periods, empty strings.
      return Double.NaN;
    }
  }
}