xstring.java

java1.6众多例子参考

      return str().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 str().equalsIgnoreCase(anotherString);
  }

  /**
   * 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 = this.length();
    int len2 = xstr.length();
    int n = Math.min(len1, len2);
    int i = 0;
    int j = 0;

    while (n-- != 0)
    {
      char c1 = this.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   str   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 str)
  {
    // %REVIEW%  Like it says, @since 1.2. Doesn't exist in earlier
    // versions of Java, hence we can't yet shell out to it. We can implement
    // it as character-by-character compare, but doing so efficiently
    // is likely to be (ahem) interesting.
    //  
    // However, since nobody is actually _using_ this method yet:
    //    return str().compareToIgnoreCase(str.toString());
    
    throw new com.sun.org.apache.xml.internal.utils.WrappedRuntimeException(
      new java.lang.NoSuchMethodException(
        "Java 1.2 method, not yet implemented"));
  }

  /**
   * 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(String prefix, int toffset)
  {
    return str().startsWith(prefix, toffset);
  }

  /**
   * 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>.
   */
  public boolean startsWith(String prefix)
  {
    return startsWith(prefix, 0);
  }

  /**
   * 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)
  {

    int to = toffset;
    int tlim = this.length();
    int po = 0;
    int pc = prefix.length();

    // Note: toffset might be near -1>>>1.
    if ((toffset < 0) || (toffset > tlim - pc))
    {
      return false;
    }

    while (--pc >= 0)
    {
      if (this.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>.
   */
  public boolean startsWith(XMLString prefix)
  {
    return startsWith(prefix, 0);
  }

  /**
   * Tests if this string ends with the specified suffix.
   *
   * @param   suffix   the suffix.
   * @return  <code>true</code> if the character sequence represented by the
   *          argument is a suffix of the character sequence represented by
   *          this object; <code>false</code> otherwise. Note that the
   *          result will be <code>true</code> if the argument is the
   *          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>suffix</code> is
   *          <code>null</code>.
   */
  public boolean endsWith(String suffix)
  {
    return str().endsWith(suffix);
  }

  /**
   * 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()
  {
    return str().hashCode();
  }

  /**
   * 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 str().indexOf(ch);
  }

  /**
   * 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)
  {
    return str().indexOf(ch, fromIndex);
  }

  /**
   * Returns the index within this string of the last occurrence of the
   * specified character. That is, the index returned is the largest
   * value <i>k</i> such that:
   * <blockquote><pre>
   * this.charAt(<i>k</i>) == ch
   * </pre></blockquote>
   * is true.
   * The String is searched backwards starting at the last character.
   *
   * @param   ch   a character.
   * @return  the index of the last occurrence of the character in the
   *          character sequence represented by this object, or
   *          <code>-1</code> if the character does not occur.
   */
  public int lastIndexOf(int ch)
  {
    return str().lastIndexOf(ch);
  }

  /**
   * Returns the index within this string of the last occurrence of the
   * specified character, searching backward starting at the specified
   * index. That is, the index returned is the largest value <i>k</i>
   * such that:
   * <blockquote><pre>
   * this.charAt(k) == ch) && (k <= fromIndex)
   * </pre></blockquote>
   * is true.
   *
   * @param   ch          a character.
   * @param   fromIndex   the index to start the search from. There is no
   *          restriction on the value of <code>fromIndex</code>. If it is
   *          greater than or equal to the length of this string, it has
   *          the same effect as if it were equal to one less than the
   *          length of this string: this entire string may be searched.
   *          If it is negative, it has the same effect as if it were -1:
   *          -1 is returned.
   * @return  the index of the last occurrence of the character in the
   *          character sequence represented by this object that is less
   *          than or equal to <code>fromIndex</code>, or <code>-1</code>
   *          if the character does not occur before that point.
   */
  public int lastIndexOf(int ch, int fromIndex)
  {
    return str().lastIndexOf(ch, fromIndex);
  }

  /**
   * Returns the index within this string of the first occurrence of the
   * specified substring. The integer returned is the smallest value
   * <i>k</i> such that:
   * <blockquote><pre>
   * this.startsWith(str, <i>k</i>)
   * </pre></blockquote>
   * is <code>true</code>.
   *
   * @param   str   any string.
   * @return  if the string argument occurs as a substring within this
   *          object, then the index of the first character of the first
   *          such substring is returned; if it does not occur as a
   *          substring, <code>-1</code> is returned.
   * @exception java.lang.NullPointerException if <code>str</code> is
   *          <code>null</code>.
   */
  public int indexOf(String str)
  {
    return str().indexOf(str);
  }

  /**
   * Returns the index within this string of the first occurrence of the
   * specified substring. The integer returned is the smallest value