string.java

来自「Mac OS X 10.4.9 for x86 Source Code gcc」· Java 代码 · 共 1,258 行 · 第 1/3 页

   * @return new String which is a substring of this String
   * @throws IndexOutOfBoundsException if begin < 0 || end > length()
   *         || begin > end (while unspecified, this is a
   *         StringIndexOutOfBoundsException)
   */
  public native String substring(int begin, int end);

  /**
   * Creates a substring of this String, starting at a specified index
   * and ending at one character before a specified index. This behaves like
   * <code>substring(begin, end)</code>.
   *
   * @param begin index to start substring (inclusive, base 0)
   * @param end index to end at (exclusive)
   * @return new String which is a substring of this String
   * @throws IndexOutOfBoundsException if begin &lt; 0 || end &gt; length()
   *         || begin &gt; end
   * @since 1.4
   */
  public CharSequence subSequence(int begin, int end)
  {
    return substring(begin, end);
  }

  /**
   * Concatenates a String to this String. This results in a new string unless
   * one of the two originals is "".
   *
   * @param str String to append to this String
   * @return newly concatenated String
   * @throws NullPointerException if str is null
   */
  public native String concat(String str);

  /**
   * Replaces every instance of a character in this String with a new
   * character. If no replacements occur, this is returned.
   *
   * @param oldChar the old character to replace
   * @param newChar the new character
   * @return new String with all instances of oldChar replaced with newChar
   */
  public native String replace(char oldChar, char newChar);

  /**
   * Test if this String matches a regular expression. This is shorthand for
   * <code>{@link Pattern}.matches(regex, this)</code>.
   *
   * @param regex the pattern to match
   * @return true if the pattern matches
   * @throws NullPointerException if regex is null
   * @throws PatternSyntaxException if regex is invalid
   * @see Pattern#matches(String, CharSequence)
   * @since 1.4
   */
  public boolean matches(String regex)
  {
    return Pattern.matches(regex, this);
  }

  /**
   * Replaces the first substring match of the regular expression with a
   * given replacement. This is shorthand for <code>{@link Pattern}
   *   .compile(regex).matcher(this).replaceFirst(replacement)</code>.
   *
   * @param regex the pattern to match
   * @param replacement the replacement string
   * @return the modified string
   * @throws NullPointerException if regex or replacement is null
   * @throws PatternSyntaxException if regex is invalid
   * @see #replaceAll(String, String)
   * @see Pattern#compile(String)
   * @see Pattern#matcher(CharSequence)
   * @see Matcher#replaceFirst(String)
   * @since 1.4
   */
  public String replaceFirst(String regex, String replacement)
  {
    return Pattern.compile(regex).matcher(this).replaceFirst(replacement);
  }

  /**
   * Replaces all matching substrings of the regular expression with a
   * given replacement. This is shorthand for <code>{@link Pattern}
   *   .compile(regex).matcher(this).replaceAll(replacement)</code>.
   *
   * @param regex the pattern to match
   * @param replacement the replacement string
   * @return the modified string
   * @throws NullPointerException if regex or replacement is null
   * @throws PatternSyntaxException if regex is invalid
   * @see #replaceFirst(String, String)
   * @see Pattern#compile(String)
   * @see Pattern#matcher(CharSequence)
   * @see Matcher#replaceAll(String)
   * @since 1.4
   */
  public String replaceAll(String regex, String replacement)
  {
    return Pattern.compile(regex).matcher(this).replaceAll(replacement);
  }

  /**
   * Split this string around the matches of a regular expression. Each
   * element of the returned array is the largest block of characters not
   * terminated by the regular expression, in the order the matches are found.
   *
   * <p>The limit affects the length of the array. If it is positive, the
   * array will contain at most n elements (n - 1 pattern matches). If
   * negative, the array length is unlimited, but there can be trailing empty
   * entries. if 0, the array length is unlimited, and trailing empty entries
   * are discarded.
   *
   * <p>For example, splitting "boo:and:foo" yields:<br>
   * <table border=0>
   * <th><td>Regex</td> <td>Limit</td> <td>Result</td></th>
   * <tr><td>":"</td>   <td>2</td>  <td>{ "boo", "and:foo" }</td></tr>
   * <tr><td>":"</td>   <td>t</td>  <td>{ "boo", "and", "foo" }</td></tr>
   * <tr><td>":"</td>   <td>-2</td> <td>{ "boo", "and", "foo" }</td></tr>
   * <tr><td>"o"</td>   <td>5</td>  <td>{ "b", "", ":and:f", "", "" }</td></tr>
   * <tr><td>"o"</td>   <td>-2</td> <td>{ "b", "", ":and:f", "", "" }</td></tr>
   * <tr><td>"o"</td>   <td>0</td>  <td>{ "b", "", ":and:f" }</td></tr>
   * </table>
   *
   * <p>This is shorthand for
   * <code>{@link Pattern}.compile(regex).split(this, limit)</code>.
   *
   * @param regex the pattern to match
   * @param limit the limit threshold
   * @return the array of split strings
   * @throws NullPointerException if regex or replacement is null
   * @throws PatternSyntaxException if regex is invalid
   * @see Pattern#compile(String)
   * @see Pattern#split(CharSequence, int)
   * @since 1.4
   */
  public String[] split(String regex, int limit)
  {
    return Pattern.compile(regex).split(this, limit);
  }

  /**
   * Split this string around the matches of a regular expression. Each
   * element of the returned array is the largest block of characters not
   * terminated by the regular expression, in the order the matches are found.
   * The array length is unlimited, and trailing empty entries are discarded,
   * as though calling <code>split(regex, 0)</code>.
   *
   * @param regex the pattern to match
   * @return the array of split strings
   * @throws NullPointerException if regex or replacement is null
   * @throws PatternSyntaxException if regex is invalid
   * @see #split(String, int)
   * @see Pattern#compile(String)
   * @see Pattern#split(CharSequence, int)
   * @since 1.4
   */
  public String[] split(String regex)
  {
    return Pattern.compile(regex).split(this, 0);
  }

  /**
   * Lowercases this String according to a particular locale. This uses
   * Unicode's special case mappings, as applied to the given Locale, so the
   * resulting string may be a different length.
   *
   * @param loc locale to use
   * @return new lowercased String, or this if no characters were lowercased
   * @throws NullPointerException if loc is null
   * @see #toUpperCase(Locale)
   * @since 1.1
   */
  public native String toLowerCase(Locale locale);

  /**
   * Lowercases this String. This uses Unicode's special case mappings, as
   * applied to the platform's default Locale, so the resulting string may
   * be a different length.
   *
   * @return new lowercased String, or this if no characters were lowercased
   * @see #toLowerCase(Locale)
   * @see #toUpperCase()
   */
  public String toLowerCase()
  {
    // The JDK is a bit confused about what to do here.  If we pass in
    // the default Locale then special Locale handling might be
    // invoked.  However, the docs also say that Character.toLowerCase
    // rules here.  We go with the latter.
    return toLowerCase (null);
  }

  /**
   * Uppercases this String according to a particular locale. This uses
   * Unicode's special case mappings, as applied to the given Locale, so the
   * resulting string may be a different length.
   *
   * @param loc locale to use
   * @return new uppercased String, or this if no characters were uppercased
   * @throws NullPointerException if loc is null
   * @see #toLowerCase(Locale)
   * @since 1.1
   */
  public native String toUpperCase(Locale locale);

  /**
   * Uppercases this String. This uses Unicode's special case mappings, as
   * applied to the platform's default Locale, so the resulting string may
   * be a different length.
   *
   * @return new uppercased String, or this if no characters were uppercased
   * @see #toUpperCase(Locale)
   * @see #toLowerCase()
   */
  public String toUpperCase()
  {
    // The JDK is a bit confused about what to do here.  If we pass in
    // the default Locale then special Locale handling might be
    // invoked.  However, the docs also say that Character.toLowerCase
    // rules here.  We go with the latter.
    return toUpperCase (null);
  }

  /**
   * Trims all characters less than or equal to <code>'\u0020'</code>
   * (<code>' '</code>) from the beginning and end of this String. This
   * includes many, but not all, ASCII control characters, and all
   * {@link Character#whitespace(char)}.
   *
   * @return new trimmed String, or this if nothing trimmed
   */
  public native String trim();

  /**
   * Returns this, as it is already a String!
   *
   * @return this
   */
  public String toString()
  {
    return this;
  }

  /**
   * Copies the contents of this String into a character array. Subsequent
   * changes to the array do not affect the String.
   *
   * @return character array copying the String
   */
  public native char[] toCharArray();

  /**
   * Returns a String representation of an Object. This is "null" if the
   * object is null, otherwise it is <code>obj.toString()</code> (which
   * can be null).
   *
   * @param obj the Object
   * @return the string conversion of obj
   */
  public static String valueOf(Object obj)
  {
    return obj == null ? "null" : obj.toString();
  }

  /**
   * Returns a String representation of a character array. Subsequent
   * changes to the array do not affect the String.
   *
   * @param data the character array
   * @return a String containing the same character sequence as data
   * @throws NullPointerException if data is null
   * @see #valueOf(char[], int, int)
   * @see #String(char[])
   */
  public static String valueOf(char[] data)
  {
    return valueOf (data, 0, data.length);
  }

  /**
   * Returns a String representing the character sequence of the char array,
   * starting at the specified offset, and copying chars up to the specified
   * count. Subsequent changes to the array do not affect the String.
   *
   * @param data character array
   * @param offset position (base 0) to start copying out of data
   * @param count the number of characters from data to copy
   * @return String containing the chars from data[offset..offset+count]
   * @throws NullPointerException if data is null
   * @throws IndexOutOfBoundsException if (offset &lt; 0 || count &lt; 0
   *         || offset + count &gt; data.length)
   *         (while unspecified, this is a StringIndexOutOfBoundsException)
   * @see #String(char[], int, int)
   */
  public static native String valueOf(char[] data, int offset, int count);

  /**
   * Returns a String representing the character sequence of the char array,
   * starting at the specified offset, and copying chars up to the specified
   * count. Subsequent changes to the array do not affect the String.
   *
   * @param data character array
   * @param offset position (base 0) to start copying out of data
   * @param count the number of characters from data to copy
   * @return String containing the chars from data[offset..offset+count]
   * @throws NullPointerException if data is null
   * @throws IndexOutOfBoundsException if (offset &lt; 0 || count &lt; 0
   *         || offset + count &gt; data.length)
   *         (while unspecified, this is a StringIndexOutOfBoundsException)
   * @see #String(char[], int, int)
   */
  public static String copyValueOf(char[] data, int offset, int count)
  {
    String r = new String ();
    r.init(data, offset, count, false);
    return r;
  }

  /**
   * Returns a String representation of a character array. Subsequent
   * changes to the array do not affect the String.
   *
   * @param data the character array
   * @return a String containing the same character sequence as data
   * @throws NullPointerException if data is null
   * @see #copyValueOf(char[], int, int)
   * @see #String(char[])
   */
  public static String copyValueOf(char[] data)
  {
    return copyValueOf (data, 0, data.length);
  }

  /**
   * Returns a String representing a boolean.
   *
   * @param b the boolean
   * @return "true" if b is true, else "false"
   */
  public static String valueOf(boolean b)
  {
    return b ? "true" : "false";
  }

  /**
   * Returns a String representing a character.
   *
   * @param c the character
   * @return String containing the single character c
   */
  public static native String valueOf(char c);

  /**
   * Returns a String representing an integer.
   *
   * @param i the integer
   * @return String containing the integer in base 10
   * @see Integer#toString(int)
   */
  public static native String valueOf(int i);

  /**
   * Returns a String representing a long.
   *
   * @param l the long
   * @return String containing the long in base 10
   * @see Long#toString(long)
   */
  public static String valueOf(long l)
  {
    return Long.toString(l);
  }

  /**
   * Returns a String representing a float.
   *
   * @param f the float
   * @return String containing the float
   * @see Float#toString(float)
   */
  public static String valueOf(float f)
  {
    return Float.toString(f);
  }

  /**
   * Returns a String representing a double.
   *
   * @param d the double
   * @return String containing the double
   * @see Double#toString(double)
   */
  public static String valueOf(double d)
  {
    return Double.toString(d);
  }

  /**
   * Fetches this String from the intern hashtable. If two Strings are
   * considered equal, by the equals() method, then intern() will return the
   * same String instance. ie. if (s1.equals(s2)) then
   * (s1.intern() == s2.intern()). All string literals and string-valued
   * constant expressions are already interned.
   *
   * @return the interned String
   */
  public native String intern();


  private native void init(char[] chars, int offset, int count,
			   boolean dont_copy);
  private native void init(byte[] chars, int hibyte, int offset, int count);
  private native void init(byte[] chars, int offset, int count, String enc)
    throws UnsupportedEncodingException;
  private native void init(gnu.gcj.runtime.StringBuffer buffer);
}