001 /* Integer.java -- object wrapper for int
002 Copyright (C) 1998, 1999, 2001, 2002, 2004, 2005
003 Free Software Foundation, Inc.
004
005 This file is part of GNU Classpath.
006
007 GNU Classpath is free software; you can redistribute it and/or modify
008 it under the terms of the GNU General Public License as published by
009 the Free Software Foundation; either version 2, or (at your option)
010 any later version.
011
012 GNU Classpath is distributed in the hope that it will be useful, but
013 WITHOUT ANY WARRANTY; without even the implied warranty of
014 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
015 General Public License for more details.
016
017 You should have received a copy of the GNU General Public License
018 along with GNU Classpath; see the file COPYING. If not, write to the
019 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
020 02110-1301 USA.
021
022 Linking this library statically or dynamically with other modules is
023 making a combined work based on this library. Thus, the terms and
024 conditions of the GNU General Public License cover the whole
025 combination.
026
027 As a special exception, the copyright holders of this library give you
028 permission to link this library with independent modules to produce an
029 executable, regardless of the license terms of these independent
030 modules, and to copy and distribute the resulting executable under
031 terms of your choice, provided that you also meet, for each linked
032 independent module, the terms and conditions of the license of that
033 module. An independent module is a module which is not derived from
034 or based on this library. If you modify this library, you may extend
035 this exception to your version of the library, but you are not
036 obligated to do so. If you do not wish to do so, delete this
037 exception statement from your version. */
038
039
040 package java.lang;
041
042 /**
043 * Instances of class <code>Integer</code> represent primitive
044 * <code>int</code> values.
045 *
046 * Additionally, this class provides various helper functions and variables
047 * related to ints.
048 *
049 * @author Paul Fisher
050 * @author John Keiser
051 * @author Warren Levy
052 * @author Eric Blake (ebb9@email.byu.edu)
053 * @author Tom Tromey (tromey@redhat.com)
054 * @author Andrew John Hughes (gnu_andrew@member.fsf.org)
055 * @author Ian Rogers
056 * @since 1.0
057 * @status updated to 1.5
058 */
059 public final class Integer extends Number implements Comparable<Integer>
060 {
061 /**
062 * Compatible with JDK 1.0.2+.
063 */
064 private static final long serialVersionUID = 1360826667806852920L;
065
066 /**
067 * The minimum value an <code>int</code> can represent is -2147483648 (or
068 * -2<sup>31</sup>).
069 */
070 public static final int MIN_VALUE = 0x80000000;
071
072 /**
073 * The maximum value an <code>int</code> can represent is 2147483647 (or
074 * 2<sup>31</sup> - 1).
075 */
076 public static final int MAX_VALUE = 0x7fffffff;
077
078 /**
079 * The primitive type <code>int</code> is represented by this
080 * <code>Class</code> object.
081 * @since 1.1
082 */
083 public static final Class<Integer> TYPE = (Class<Integer>) VMClassLoader.getPrimitiveClass('I');
084
085 /**
086 * The number of bits needed to represent an <code>int</code>.
087 * @since 1.5
088 */
089 public static final int SIZE = 32;
090
091 // This caches some Integer values, and is used by boxing
092 // conversions via valueOf(). We must cache at least -128..127;
093 // these constants control how much we actually cache.
094 private static final int MIN_CACHE = -128;
095 private static final int MAX_CACHE = 127;
096 private static final Integer[] intCache = new Integer[MAX_CACHE - MIN_CACHE + 1];
097 static
098 {
099 for (int i=MIN_CACHE; i <= MAX_CACHE; i++)
100 intCache[i - MIN_CACHE] = new Integer(i);
101 }
102
103 /**
104 * The immutable value of this Integer.
105 *
106 * @serial the wrapped int
107 */
108 private final int value;
109
110 /**
111 * Create an <code>Integer</code> object representing the value of the
112 * <code>int</code> argument.
113 *
114 * @param value the value to use
115 */
116 public Integer(int value)
117 {
118 this.value = value;
119 }
120
121 /**
122 * Create an <code>Integer</code> object representing the value of the
123 * argument after conversion to an <code>int</code>.
124 *
125 * @param s the string to convert
126 * @throws NumberFormatException if the String does not contain an int
127 * @see #valueOf(String)
128 */
129 public Integer(String s)
130 {
131 value = parseInt(s, 10, false);
132 }
133
134 /**
135 * Return the size of a string large enough to hold the given number
136 *
137 * @param num the number we want the string length for (must be positive)
138 * @param radix the radix (base) that will be used for the string
139 * @return a size sufficient for a string of num
140 */
141 private static int stringSize(int num, int radix) {
142 int exp;
143 if (radix < 4)
144 {
145 exp = 1;
146 }
147 else if (radix < 8)
148 {
149 exp = 2;
150 }
151 else if (radix < 16)
152 {
153 exp = 3;
154 }
155 else if (radix < 32)
156 {
157 exp = 4;
158 }
159 else
160 {
161 exp = 5;
162 }
163 int size=0;
164 do
165 {
166 num >>>= exp;
167 size++;
168 }
169 while(num != 0);
170 return size;
171 }
172
173 /**
174 * Converts the <code>int</code> to a <code>String</code> using
175 * the specified radix (base). If the radix exceeds
176 * <code>Character.MIN_RADIX</code> or <code>Character.MAX_RADIX</code>, 10
177 * is used instead. If the result is negative, the leading character is
178 * '-' ('\\u002D'). The remaining characters come from
179 * <code>Character.forDigit(digit, radix)</code> ('0'-'9','a'-'z').
180 *
181 * @param num the <code>int</code> to convert to <code>String</code>
182 * @param radix the radix (base) to use in the conversion
183 * @return the <code>String</code> representation of the argument
184 */
185 public static String toString(int num, int radix)
186 {
187 if (radix < Character.MIN_RADIX || radix > Character.MAX_RADIX)
188 radix = 10;
189
190 // Is the value negative?
191 boolean isNeg = num < 0;
192
193 // Is the string a single character?
194 if (!isNeg && num < radix)
195 return new String(digits, num, 1, true);
196
197 // Compute string size and allocate buffer
198 // account for a leading '-' if the value is negative
199 int size;
200 int i;
201 char[] buffer;
202 if (isNeg)
203 {
204 num = -num;
205
206 // When the value is MIN_VALUE, it overflows when made positive
207 if (num < 0)
208 {
209 i = size = stringSize(MAX_VALUE, radix) + 2;
210 buffer = new char[size];
211 buffer[--i] = digits[(int) (-(num + radix) % radix)];
212 num = -(num / radix);
213 }
214 else
215 {
216 i = size = stringSize(num, radix) + 1;
217 buffer = new char[size];
218 }
219 }
220 else
221 {
222 i = size = stringSize(num, radix);
223 buffer = new char[size];
224 }
225
226 do
227 {
228 buffer[--i] = digits[num % radix];
229 num /= radix;
230 }
231 while (num > 0);
232
233 if (isNeg)
234 buffer[--i] = '-';
235
236 // Package constructor avoids an array copy.
237 return new String(buffer, i, size - i, true);
238 }
239
240 /**
241 * Converts the <code>int</code> to a <code>String</code> assuming it is
242 * unsigned in base 16.
243 *
244 * @param i the <code>int</code> to convert to <code>String</code>
245 * @return the <code>String</code> representation of the argument
246 */
247 public static String toHexString(int i)
248 {
249 return toUnsignedString(i, 4);
250 }
251
252 /**
253 * Converts the <code>int</code> to a <code>String</code> assuming it is
254 * unsigned in base 8.
255 *
256 * @param i the <code>int</code> to convert to <code>String</code>
257 * @return the <code>String</code> representation of the argument
258 */
259 public static String toOctalString(int i)
260 {
261 return toUnsignedString(i, 3);
262 }
263
264 /**
265 * Converts the <code>int</code> to a <code>String</code> assuming it is
266 * unsigned in base 2.
267 *
268 * @param i the <code>int</code> to convert to <code>String</code>
269 * @return the <code>String</code> representation of the argument
270 */
271 public static String toBinaryString(int i)
272 {
273 return toUnsignedString(i, 1);
274 }
275
276 /**
277 * Converts the <code>int</code> to a <code>String</code> and assumes
278 * a radix of 10.
279 *
280 * @param i the <code>int</code> to convert to <code>String</code>
281 * @return the <code>String</code> representation of the argument
282 * @see #toString(int, int)
283 */
284 public static String toString(int i)
285 {
286 // This is tricky: in libgcj, String.valueOf(int) is a fast native
287 // implementation. In Classpath it just calls back to
288 // Integer.toString(int, int).
289 return String.valueOf(i);
290 }
291
292 /**
293 * Converts the specified <code>String</code> into an <code>int</code>
294 * using the specified radix (base). The string must not be <code>null</code>
295 * or empty. It may begin with an optional '-', which will negate the answer,
296 * provided that there are also valid digits. Each digit is parsed as if by
297 * <code>Character.digit(d, radix)</code>, and must be in the range
298 * <code>0</code> to <code>radix - 1</code>. Finally, the result must be
299 * within <code>MIN_VALUE</code> to <code>MAX_VALUE</code>, inclusive.
300 * Unlike Double.parseDouble, you may not have a leading '+'.
301 *
302 * @param str the <code>String</code> to convert
303 * @param radix the radix (base) to use in the conversion
304 * @return the <code>String</code> argument converted to <code>int</code>
305 * @throws NumberFormatException if <code>s</code> cannot be parsed as an
306 * <code>int</code>
307 */
308 public static int parseInt(String str, int radix)
309 {
310 return parseInt(str, radix, false);
311 }
312
313 /**
314 * Converts the specified <code>String</code> into an <code>int</code>.
315 * This function assumes a radix of 10.
316 *
317 * @param s the <code>String</code> to convert
318 * @return the <code>int</code> value of <code>s</code>
319 * @throws NumberFormatException if <code>s</code> cannot be parsed as an
320 * <code>int</code>
321 * @see #parseInt(String, int)
322 */
323 public static int parseInt(String s)
324 {
325 return parseInt(s, 10, false);
326 }
327
328 /**
329 * Creates a new <code>Integer</code> object using the <code>String</code>
330 * and specified radix (base).
331 *
332 * @param s the <code>String</code> to convert
333 * @param radix the radix (base) to convert with
334 * @return the new <code>Integer</code>
335 * @throws NumberFormatException if <code>s</code> cannot be parsed as an
336 * <code>int</code>
337 * @see #parseInt(String, int)
338 */
339 public static Integer valueOf(String s, int radix)
340 {
341 return valueOf(parseInt(s, radix, false));
342 }
343
344 /**
345 * Creates a new <code>Integer</code> object using the <code>String</code>,
346 * assuming a radix of 10.
347 *
348 * @param s the <code>String</code> to convert
349 * @return the new <code>Integer</code>
350 * @throws NumberFormatException if <code>s</code> cannot be parsed as an
351 * <code>int</code>
352 * @see #Integer(String)
353 * @see #parseInt(String)
354 */
355 public static Integer valueOf(String s)
356 {
357 return valueOf(parseInt(s, 10, false));
358 }
359
360 /**
361 * Returns an <code>Integer</code> object wrapping the value.
362 * In contrast to the <code>Integer</code> constructor, this method
363 * will cache some values. It is used by boxing conversion.
364 *
365 * @param val the value to wrap
366 * @return the <code>Integer</code>
367 */
368 public static Integer valueOf(int val)
369 {
370 if (val < MIN_CACHE || val > MAX_CACHE)
371 return new Integer(val);
372 else
373 return intCache[val - MIN_CACHE];
374 }
375
376 /**
377 * Return the value of this <code>Integer</code> as a <code>byte</code>.
378 *
379 * @return the byte value
380 */
381 public byte byteValue()
382 {
383 return (byte) value;
384 }
385
386 /**
387 * Return the value of this <code>Integer</code> as a <code>short</code>.
388 *
389 * @return the short value
390 */
391 public short shortValue()
392 {
393 return (short) value;
394 }
395
396 /**
397 * Return the value of this <code>Integer</code>.
398 * @return the int value
399 */
400 public int intValue()
401 {
402 return value;
403 }
404
405 /**
406 * Return the value of this <code>Integer</code> as a <code>long</code>.
407 *
408 * @return the long value
409 */
410 public long longValue()
411 {
412 return value;
413 }
414
415 /**
416 * Return the value of this <code>Integer</code> as a <code>float</code>.
417 *
418 * @return the float value
419 */
420 public float floatValue()
421 {
422 return value;
423 }
424
425 /**
426 * Return the value of this <code>Integer</code> as a <code>double</code>.
427 *
428 * @return the double value
429 */
430 public double doubleValue()
431 {
432 return value;
433 }
434
435 /**
436 * Converts the <code>Integer</code> value to a <code>String</code> and
437 * assumes a radix of 10.
438 *
439 * @return the <code>String</code> representation
440 */
441 public String toString()
442 {
443 return String.valueOf(value);
444 }
445
446 /**
447 * Return a hashcode representing this Object. <code>Integer</code>'s hash
448 * code is simply its value.
449 *
450 * @return this Object's hash code
451 */
452 public int hashCode()
453 {
454 return value;
455 }
456
457 /**
458 * Returns <code>true</code> if <code>obj</code> is an instance of
459 * <code>Integer</code> and represents the same int value.
460 *
461 * @param obj the object to compare
462 * @return whether these Objects are semantically equal
463 */
464 public boolean equals(Object obj)
465 {
466 return obj instanceof Integer && value == ((Integer) obj).value;
467 }
468
469 /**
470 * Get the specified system property as an <code>Integer</code>. The
471 * <code>decode()</code> method will be used to interpret the value of
472 * the property.
473 *
474 * @param nm the name of the system property
475 * @return the system property as an <code>Integer</code>, or null if the
476 * property is not found or cannot be decoded
477 * @throws SecurityException if accessing the system property is forbidden
478 * @see System#getProperty(String)
479 * @see #decode(String)
480 */
481 public static Integer getInteger(String nm)
482 {
483 return getInteger(nm, null);
484 }
485
486 /**
487 * Get the specified system property as an <code>Integer</code>, or use a
488 * default <code>int</code> value if the property is not found or is not
489 * decodable. The <code>decode()</code> method will be used to interpret
490 * the value of the property.
491 *
492 * @param nm the name of the system property
493 * @param val the default value
494 * @return the value of the system property, or the default
495 * @throws SecurityException if accessing the system property is forbidden
496 * @see System#getProperty(String)
497 * @see #decode(String)
498 */
499 public static Integer getInteger(String nm, int val)
500 {
501 Integer result = getInteger(nm, null);
502 return result == null ? valueOf(val) : result;
503 }
504
505 /**
506 * Get the specified system property as an <code>Integer</code>, or use a
507 * default <code>Integer</code> value if the property is not found or is
508 * not decodable. The <code>decode()</code> method will be used to
509 * interpret the value of the property.
510 *
511 * @param nm the name of the system property
512 * @param def the default value
513 * @return the value of the system property, or the default
514 * @throws SecurityException if accessing the system property is forbidden
515 * @see System#getProperty(String)
516 * @see #decode(String)
517 */
518 public static Integer getInteger(String nm, Integer def)
519 {
520 if (nm == null || "".equals(nm))
521 return def;
522 nm = System.getProperty(nm);
523 if (nm == null)
524 return def;
525 try
526 {
527 return decode(nm);
528 }
529 catch (NumberFormatException e)
530 {
531 return def;
532 }
533 }
534
535 /**
536 * Convert the specified <code>String</code> into an <code>Integer</code>.
537 * The <code>String</code> may represent decimal, hexadecimal, or
538 * octal numbers.
539 *
540 * <p>The extended BNF grammar is as follows:<br>
541 * <pre>
542 * <em>DecodableString</em>:
543 * ( [ <code>-</code> ] <em>DecimalNumber</em> )
544 * | ( [ <code>-</code> ] ( <code>0x</code> | <code>0X</code>
545 * | <code>#</code> ) <em>HexDigit</em> { <em>HexDigit</em> } )
546 * | ( [ <code>-</code> ] <code>0</code> { <em>OctalDigit</em> } )
547 * <em>DecimalNumber</em>:
548 * <em>DecimalDigit except '0'</em> { <em>DecimalDigit</em> }
549 * <em>DecimalDigit</em>:
550 * <em>Character.digit(d, 10) has value 0 to 9</em>
551 * <em>OctalDigit</em>:
552 * <em>Character.digit(d, 8) has value 0 to 7</em>
553 * <em>DecimalDigit</em>:
554 * <em>Character.digit(d, 16) has value 0 to 15</em>
555 * </pre>
556 * Finally, the value must be in the range <code>MIN_VALUE</code> to
557 * <code>MAX_VALUE</code>, or an exception is thrown.
558 *
559 * @param str the <code>String</code> to interpret
560 * @return the value of the String as an <code>Integer</code>
561 * @throws NumberFormatException if <code>s</code> cannot be parsed as a
562 * <code>int</code>
563 * @throws NullPointerException if <code>s</code> is null
564 * @since 1.2
565 */
566 public static Integer decode(String str)
567 {
568 return valueOf(parseInt(str, 10, true));
569 }
570
571 /**
572 * Compare two Integers numerically by comparing their <code>int</code>
573 * values. The result is positive if the first is greater, negative if the
574 * second is greater, and 0 if the two are equal.
575 *
576 * @param i the Integer to compare
577 * @return the comparison
578 * @since 1.2
579 */
580 public int compareTo(Integer i)
581 {
582 if (value == i.value)
583 return 0;
584 // Returns just -1 or 1 on inequality; doing math might overflow.
585 return value > i.value ? 1 : -1;
586 }
587
588 /**
589 * Return the number of bits set in x.
590 * @param x value to examine
591 * @since 1.5
592 */
593 public static int bitCount(int x)
594 {
595 // Successively collapse alternating bit groups into a sum.
596 x = ((x >> 1) & 0x55555555) + (x & 0x55555555);
597 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
598 x = ((x >> 4) & 0x0f0f0f0f) + (x & 0x0f0f0f0f);
599 x = ((x >> 8) & 0x00ff00ff) + (x & 0x00ff00ff);
600 return ((x >> 16) & 0x0000ffff) + (x & 0x0000ffff);
601 }
602
603 /**
604 * Rotate x to the left by distance bits.
605 * @param x the value to rotate
606 * @param distance the number of bits by which to rotate
607 * @since 1.5
608 */
609 public static int rotateLeft(int x, int distance)
610 {
611 // This trick works because the shift operators implicitly mask
612 // the shift count.
613 return (x << distance) | (x >>> - distance);
614 }
615
616 /**
617 * Rotate x to the right by distance bits.
618 * @param x the value to rotate
619 * @param distance the number of bits by which to rotate
620 * @since 1.5
621 */
622 public static int rotateRight(int x, int distance)
623 {
624 // This trick works because the shift operators implicitly mask
625 // the shift count.
626 return (x << - distance) | (x >>> distance);
627 }
628
629 /**
630 * Find the highest set bit in value, and return a new value
631 * with only that bit set.
632 * @param value the value to examine
633 * @since 1.5
634 */
635 public static int highestOneBit(int value)
636 {
637 value |= value >>> 1;
638 value |= value >>> 2;
639 value |= value >>> 4;
640 value |= value >>> 8;
641 value |= value >>> 16;
642 return value ^ (value >>> 1);
643 }
644
645 /**
646 * Return the number of leading zeros in value.
647 * @param value the value to examine
648 * @since 1.5
649 */
650 public static int numberOfLeadingZeros(int value)
651 {
652 value |= value >>> 1;
653 value |= value >>> 2;
654 value |= value >>> 4;
655 value |= value >>> 8;
656 value |= value >>> 16;
657 return bitCount(~value);
658 }
659
660 /**
661 * Find the lowest set bit in value, and return a new value
662 * with only that bit set.
663 * @param value the value to examine
664 * @since 1.5
665 */
666 public static int lowestOneBit(int value)
667 {
668 // Classic assembly trick.
669 return value & - value;
670 }
671
672 /**
673 * Find the number of trailing zeros in value.
674 * @param value the value to examine
675 * @since 1.5
676 */
677 public static int numberOfTrailingZeros(int value)
678 {
679 return bitCount((value & -value) - 1);
680 }
681
682 /**
683 * Return 1 if x is positive, -1 if it is negative, and 0 if it is
684 * zero.
685 * @param x the value to examine
686 * @since 1.5
687 */
688 public static int signum(int x)
689 {
690 return (x >> 31) | (-x >>> 31);
691
692 // The LHS propagates the sign bit through every bit in the word;
693 // if X < 0, every bit is set to 1, else 0. if X > 0, the RHS
694 // negates x and shifts the resulting 1 in the sign bit to the
695 // LSB, leaving every other bit 0.
696
697 // Hacker's Delight, Section 2-7
698 }
699
700 /**
701 * Reverse the bytes in val.
702 * @since 1.5
703 */
704 public static int reverseBytes(int val)
705 {
706 return ( ((val >> 24) & 0xff)
707 | ((val >> 8) & 0xff00)
708 | ((val << 8) & 0xff0000)
709 | ((val << 24) & 0xff000000));
710 }
711
712 /**
713 * Reverse the bits in val.
714 * @since 1.5
715 */
716 public static int reverse(int val)
717 {
718 // Successively swap alternating bit groups.
719 val = ((val >> 1) & 0x55555555) + ((val << 1) & ~0x55555555);
720 val = ((val >> 2) & 0x33333333) + ((val << 2) & ~0x33333333);
721 val = ((val >> 4) & 0x0f0f0f0f) + ((val << 4) & ~0x0f0f0f0f);
722 val = ((val >> 8) & 0x00ff00ff) + ((val << 8) & ~0x00ff00ff);
723 return ((val >> 16) & 0x0000ffff) + ((val << 16) & ~0x0000ffff);
724 }
725
726 /**
727 * Helper for converting unsigned numbers to String.
728 *
729 * @param num the number
730 * @param exp log2(digit) (ie. 1, 3, or 4 for binary, oct, hex)
731 */
732 // Package visible for use by Long.
733 static String toUnsignedString(int num, int exp)
734 {
735 // Compute string length
736 int size = 1;
737 int copy = num >>> exp;
738 while (copy != 0)
739 {
740 size++;
741 copy >>>= exp;
742 }
743 // Quick path for single character strings
744 if (size == 1)
745 return new String(digits, num, 1, true);
746
747 // Encode into buffer
748 int mask = (1 << exp) - 1;
749 char[] buffer = new char[size];
750 int i = size;
751 do
752 {
753 buffer[--i] = digits[num & mask];
754 num >>>= exp;
755 }
756 while (num != 0);
757
758 // Package constructor avoids an array copy.
759 return new String(buffer, i, size - i, true);
760 }
761
762 /**
763 * Helper for parsing ints, used by Integer, Short, and Byte.
764 *
765 * @param str the string to parse
766 * @param radix the radix to use, must be 10 if decode is true
767 * @param decode if called from decode
768 * @return the parsed int value
769 * @throws NumberFormatException if there is an error
770 * @throws NullPointerException if decode is true and str if null
771 * @see #parseInt(String, int)
772 * @see #decode(String)
773 * @see Byte#parseByte(String, int)
774 * @see Short#parseShort(String, int)
775 */
776 static int parseInt(String str, int radix, boolean decode)
777 {
778 if (! decode && str == null)
779 throw new NumberFormatException();
780 int index = 0;
781 int len = str.length();
782 boolean isNeg = false;
783 if (len == 0)
784 throw new NumberFormatException("string length is null");
785 int ch = str.charAt(index);
786 if (ch == '-')
787 {
788 if (len == 1)
789 throw new NumberFormatException("pure '-'");
790 isNeg = true;
791 ch = str.charAt(++index);
792 }
793 else if (ch == '+')
794 {
795 if (len == 1)
796 throw new NumberFormatException("pure '+'");
797 ch = str.charAt(++index);
798 }
799 if (decode)
800 {
801 if (ch == '0')
802 {
803 if (++index == len)
804 return 0;
805 if ((str.charAt(index) & ~('x' ^ 'X')) == 'X')
806 {
807 radix = 16;
808 index++;
809 }
810 else
811 radix = 8;
812 }
813 else if (ch == '#')
814 {
815 radix = 16;
816 index++;
817 }
818 }
819 if (index == len)
820 throw new NumberFormatException("non terminated number: " + str);
821
822 int max = MAX_VALUE / radix;
823 // We can't directly write `max = (MAX_VALUE + 1) / radix'.
824 // So instead we fake it.
825 if (isNeg && MAX_VALUE % radix == radix - 1)
826 ++max;
827
828 int val = 0;
829 while (index < len)
830 {
831 if (val < 0 || val > max)
832 throw new NumberFormatException("number overflow (pos=" + index + ") : " + str);
833
834 ch = Character.digit(str.charAt(index++), radix);
835 val = val * radix + ch;
836 if (ch < 0 || (val < 0 && (! isNeg || val != MIN_VALUE)))
837 throw new NumberFormatException("invalid character at position " + index + " in " + str);
838 }
839 return isNeg ? -val : val;
840 }
841 }