1 /*
2 * Copyright (C) 2008 The Guava Authors
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
5 * in compliance with the License. You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software distributed under the License
10 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
11 * or implied. See the License for the specific language governing permissions and limitations under
12 * the License.
13 */
14
15 package com.google.common.primitives;
16
17 import static com.google.common.base.Preconditions.checkArgument;
18 import static com.google.common.base.Preconditions.checkElementIndex;
19 import static com.google.common.base.Preconditions.checkNotNull;
20 import static com.google.common.base.Preconditions.checkPositionIndexes;
21
22 import com.google.common.annotations.Beta;
23 import com.google.common.annotations.GwtCompatible;
24 import com.google.common.base.Converter;
25 import java.io.Serializable;
26 import java.util.AbstractList;
27 import java.util.Arrays;
28 import java.util.Collection;
29 import java.util.Collections;
30 import java.util.Comparator;
31 import java.util.List;
32 import java.util.RandomAccess;
33 import java.util.Spliterator;
34 import java.util.Spliterators;
35 import javax.annotation.CheckForNull;
36
37 /**
38 * Static utility methods pertaining to {@code long} primitives, that are not already found in
39 * either {@link Long} or {@link Arrays}.
40 *
41 * <p>See the Guava User Guide article on <a
42 * href="https://github.com/google/guava/wiki/PrimitivesExplained">primitive utilities</a>.
43 *
44 * @author Kevin Bourrillion
45 * @since 1.0
46 */
47 @GwtCompatible
48 @ElementTypesAreNonnullByDefault
49 public final class Longs {
50 private Longs() {}
51
52 /**
53 * The number of bytes required to represent a primitive {@code long} value.
54 *
55 * <p><b>Java 8 users:</b> use {@link Long#BYTES} instead.
56 */
57 public static final int BYTES = Long.SIZE / Byte.SIZE;
58
59 /**
60 * The largest power of two that can be represented as a {@code long}.
61 *
62 * @since 10.0
63 */
64 public static final long MAX_POWER_OF_TWO = 1L << (Long.SIZE - 2);
65
66 /**
67 * Returns a hash code for {@code value}; equal to the result of invoking {@code ((Long)
68 * value).hashCode()}.
69 *
70 * <p>This method always return the value specified by {@link Long#hashCode()} in java, which
71 * might be different from {@code ((Long) value).hashCode()} in GWT because {@link
72 * Long#hashCode()} in GWT does not obey the JRE contract.
73 *
74 * <p><b>Java 8 users:</b> use {@link Long#hashCode(long)} instead.
75 *
76 * @param value a primitive {@code long} value
77 * @return a hash code for the value
78 */
79 public static int hashCode(long value) {
80 return (int) (value ^ (value >>> 32));
81 }
82
83 /**
84 * Compares the two specified {@code long} values. The sign of the value returned is the same as
85 * that of {@code ((Long) a).compareTo(b)}.
86 *
87 * <p><b>Note for Java 7 and later:</b> this method should be treated as deprecated; use the
88 * equivalent {@link Long#compare} method instead.
89 *
90 * @param a the first {@code long} to compare
91 * @param b the second {@code long} to compare
92 * @return a negative value if {@code a} is less than {@code b}; a positive value if {@code a} is
93 * greater than {@code b}; or zero if they are equal
94 */
95 public static int compare(long a, long b) {
96 return (a < b) ? -1 : ((a > b) ? 1 : 0);
97 }
98
99 /**
100 * Returns {@code true} if {@code target} is present as an element anywhere in {@code array}.
101 *
102 * @param array an array of {@code long} values, possibly empty
103 * @param target a primitive {@code long} value
104 * @return {@code true} if {@code array[i] == target} for some value of {@code i}
105 */
106 public static boolean contains(long[] array, long target) {
107 for (long value : array) {
108 if (value == target) {
109 return true;
110 }
111 }
112 return false;
113 }
114
115 /**
116 * Returns the index of the first appearance of the value {@code target} in {@code array}.
117 *
118 * @param array an array of {@code long} values, possibly empty
119 * @param target a primitive {@code long} value
120 * @return the least index {@code i} for which {@code array[i] == target}, or {@code -1} if no
121 * such index exists.
122 */
123 public static int indexOf(long[] array, long target) {
124 return indexOf(array, target, 0, array.length);
125 }
126
127 // TODO(kevinb): consider making this public
128 private static int indexOf(long[] array, long target, int start, int end) {
129 for (int i = start; i < end; i++) {
130 if (array[i] == target) {
131 return i;
132 }
133 }
134 return -1;
135 }
136
137 /**
138 * Returns the start position of the first occurrence of the specified {@code target} within
139 * {@code array}, or {@code -1} if there is no such occurrence.
140 *
141 * <p>More formally, returns the lowest index {@code i} such that {@code Arrays.copyOfRange(array,
142 * i, i + target.length)} contains exactly the same elements as {@code target}.
143 *
144 * @param array the array to search for the sequence {@code target}
145 * @param target the array to search for as a sub-sequence of {@code array}
146 */
147 public static int indexOf(long[] array, long[] target) {
148 checkNotNull(array, "array");
149 checkNotNull(target, "target");
150 if (target.length == 0) {
151 return 0;
152 }
153
154 outer:
155 for (int i = 0; i < array.length - target.length + 1; i++) {
156 for (int j = 0; j < target.length; j++) {
157 if (array[i + j] != target[j]) {
158 continue outer;
159 }
160 }
161 return i;
162 }
163 return -1;
164 }
165
166 /**
167 * Returns the index of the last appearance of the value {@code target} in {@code array}.
168 *
169 * @param array an array of {@code long} values, possibly empty
170 * @param target a primitive {@code long} value
171 * @return the greatest index {@code i} for which {@code array[i] == target}, or {@code -1} if no
172 * such index exists.
173 */
174 public static int lastIndexOf(long[] array, long target) {
175 return lastIndexOf(array, target, 0, array.length);
176 }
177
178 // TODO(kevinb): consider making this public
179 private static int lastIndexOf(long[] array, long target, int start, int end) {
180 for (int i = end - 1; i >= start; i--) {
181 if (array[i] == target) {
182 return i;
183 }
184 }
185 return -1;
186 }
187
188 /**
189 * Returns the least value present in {@code array}.
190 *
191 * @param array a <i>nonempty</i> array of {@code long} values
192 * @return the value present in {@code array} that is less than or equal to every other value in
193 * the array
194 * @throws IllegalArgumentException if {@code array} is empty
195 */
196 public static long min(long... array) {
197 checkArgument(array.length > 0);
198 long min = array[0];
199 for (int i = 1; i < array.length; i++) {
200 if (array[i] < min) {
201 min = array[i];
202 }
203 }
204 return min;
205 }
206
207 /**
208 * Returns the greatest value present in {@code array}.
209 *
210 * @param array a <i>nonempty</i> array of {@code long} values
211 * @return the value present in {@code array} that is greater than or equal to every other value
212 * in the array
213 * @throws IllegalArgumentException if {@code array} is empty
214 */
215 public static long max(long... array) {
216 checkArgument(array.length > 0);
217 long max = array[0];
218 for (int i = 1; i < array.length; i++) {
219 if (array[i] > max) {
220 max = array[i];
221 }
222 }
223 return max;
224 }
225
226 /**
227 * Returns the value nearest to {@code value} which is within the closed range {@code [min..max]}.
228 *
229 * <p>If {@code value} is within the range {@code [min..max]}, {@code value} is returned
230 * unchanged. If {@code value} is less than {@code min}, {@code min} is returned, and if {@code
231 * value} is greater than {@code max}, {@code max} is returned.
232 *
233 * @param value the {@code long} value to constrain
234 * @param min the lower bound (inclusive) of the range to constrain {@code value} to
235 * @param max the upper bound (inclusive) of the range to constrain {@code value} to
236 * @throws IllegalArgumentException if {@code min > max}
237 * @since 21.0
238 */
239 @Beta
240 public static long constrainToRange(long value, long min, long max) {
241 checkArgument(min <= max, "min (%s) must be less than or equal to max (%s)", min, max);
242 return Math.min(Math.max(value, min), max);
243 }
244
245 /**
246 * Returns the values from each provided array combined into a single array. For example, {@code
247 * concat(new long[] {a, b}, new long[] {}, new long[] {c}} returns the array {@code {a, b, c}}.
248 *
249 * @param arrays zero or more {@code long} arrays
250 * @return a single array containing all the values from the source arrays, in order
251 */
252 public static long[] concat(long[]... arrays) {
253 int length = 0;
254 for (long[] array : arrays) {
255 length += array.length;
256 }
257 long[] result = new long[length];
258 int pos = 0;
259 for (long[] array : arrays) {
260 System.arraycopy(array, 0, result, pos, array.length);
261 pos += array.length;
262 }
263 return result;
264 }
265
266 /**
267 * Returns a big-endian representation of {@code value} in an 8-element byte array; equivalent to
268 * {@code ByteBuffer.allocate(8).putLong(value).array()}. For example, the input value {@code
269 * 0x1213141516171819L} would yield the byte array {@code {0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
270 * 0x18, 0x19}}.
271 *
272 * <p>If you need to convert and concatenate several values (possibly even of different types),
273 * use a shared {@link java.nio.ByteBuffer} instance, or use {@link
274 * com.google.common.io.ByteStreams#newDataOutput()} to get a growable buffer.
275 */
276 public static byte[] toByteArray(long value) {
277 // Note that this code needs to stay compatible with GWT, which has known
278 // bugs when narrowing byte casts of long values occur.
279 byte[] result = new byte[8];
280 for (int i = 7; i >= 0; i--) {
281 result[i] = (byte) (value & 0xffL);
282 value >>= 8;
283 }
284 return result;
285 }
286
287 /**
288 * Returns the {@code long} value whose big-endian representation is stored in the first 8 bytes
289 * of {@code bytes}; equivalent to {@code ByteBuffer.wrap(bytes).getLong()}. For example, the
290 * input byte array {@code {0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19}} would yield the
291 * {@code long} value {@code 0x1213141516171819L}.
292 *
293 * <p>Arguably, it's preferable to use {@link java.nio.ByteBuffer}; that library exposes much more
294 * flexibility at little cost in readability.
295 *
296 * @throws IllegalArgumentException if {@code bytes} has fewer than 8 elements
297 */
298 public static long fromByteArray(byte[] bytes) {
299 checkArgument(bytes.length >= BYTES, "array too small: %s < %s", bytes.length, BYTES);
300 return fromBytes(
301 bytes[0], bytes[1], bytes[2], bytes[3], bytes[4], bytes[5], bytes[6], bytes[7]);
302 }
303
304 /**
305 * Returns the {@code long} value whose byte representation is the given 8 bytes, in big-endian
306 * order; equivalent to {@code Longs.fromByteArray(new byte[] {b1, b2, b3, b4, b5, b6, b7, b8})}.
307 *
308 * @since 7.0
309 */
310 public static long fromBytes(
311 byte b1, byte b2, byte b3, byte b4, byte b5, byte b6, byte b7, byte b8) {
312 return (b1 & 0xFFL) << 56
313 | (b2 & 0xFFL) << 48
314 | (b3 & 0xFFL) << 40
315 | (b4 & 0xFFL) << 32
316 | (b5 & 0xFFL) << 24
317 | (b6 & 0xFFL) << 16
318 | (b7 & 0xFFL) << 8
319 | (b8 & 0xFFL);
320 }
321
322 /*
323 * Moving asciiDigits into this static holder class lets ProGuard eliminate and inline the Longs
324 * class.
325 */
326 static final class AsciiDigits {
327 private AsciiDigits() {}
328
329 private static final byte[] asciiDigits;
330
331 static {
332 byte[] result = new byte[128];
333 Arrays.fill(result, (byte) -1);
334 for (int i = 0; i < 10; i++) {
335 result['0' + i] = (byte) i;
336 }
337 for (int i = 0; i < 26; i++) {
338 result['A' + i] = (byte) (10 + i);
339 result['a' + i] = (byte) (10 + i);
340 }
341 asciiDigits = result;
342 }
343
344 static int digit(char c) {
345 return (c < 128) ? asciiDigits[c] : -1;
346 }
347 }
348
349 /**
350 * Parses the specified string as a signed decimal long value. The ASCII character {@code '-'} (
351 * <code>'\u002D'</code>) is recognized as the minus sign.
352 *
353 * <p>Unlike {@link Long#parseLong(String)}, this method returns {@code null} instead of throwing
354 * an exception if parsing fails. Additionally, this method only accepts ASCII digits, and returns
355 * {@code null} if non-ASCII digits are present in the string.
356 *
357 * <p>Note that strings prefixed with ASCII {@code '+'} are rejected, even under JDK 7, despite
358 * the change to {@link Long#parseLong(String)} for that version.
359 *
360 * @param string the string representation of a long value
361 * @return the long value represented by {@code string}, or {@code null} if {@code string} has a
362 * length of zero or cannot be parsed as a long value
363 * @throws NullPointerException if {@code string} is {@code null}
364 * @since 14.0
365 */
366 @Beta
367 @CheckForNull
368 public static Long tryParse(String string) {
369 return tryParse(string, 10);
370 }
371
372 /**
373 * Parses the specified string as a signed long value using the specified radix. The ASCII
374 * character {@code '-'} (<code>'\u002D'</code>) is recognized as the minus sign.
375 *
376 * <p>Unlike {@link Long#parseLong(String, int)}, this method returns {@code null} instead of
377 * throwing an exception if parsing fails. Additionally, this method only accepts ASCII digits,
378 * and returns {@code null} if non-ASCII digits are present in the string.
379 *
380 * <p>Note that strings prefixed with ASCII {@code '+'} are rejected, even under JDK 7, despite
381 * the change to {@link Long#parseLong(String, int)} for that version.
382 *
383 * @param string the string representation of an long value
384 * @param radix the radix to use when parsing
385 * @return the long value represented by {@code string} using {@code radix}, or {@code null} if
386 * {@code string} has a length of zero or cannot be parsed as a long value
387 * @throws IllegalArgumentException if {@code radix < Character.MIN_RADIX} or {@code radix >
388 * Character.MAX_RADIX}
389 * @throws NullPointerException if {@code string} is {@code null}
390 * @since 19.0
391 */
392 @Beta
393 @CheckForNull
394 public static Long tryParse(String string, int radix) {
395 if (checkNotNull(string).isEmpty()) {
396 return null;
397 }
398 if (radix < Character.MIN_RADIX || radix > Character.MAX_RADIX) {
399 throw new IllegalArgumentException(
400 "radix must be between MIN_RADIX and MAX_RADIX but was " + radix);
401 }
402 boolean negative = string.charAt(0) == '-';
403 int index = negative ? 1 : 0;
404 if (index == string.length()) {
405 return null;
406 }
407 int digit = AsciiDigits.digit(string.charAt(index++));
408 if (digit < 0 || digit >= radix) {
409 return null;
410 }
411 long accum = -digit;
412
413 long cap = Long.MIN_VALUE / radix;
414
415 while (index < string.length()) {
416 digit = AsciiDigits.digit(string.charAt(index++));
417 if (digit < 0 || digit >= radix || accum < cap) {
418 return null;
419 }
420 accum *= radix;
421 if (accum < Long.MIN_VALUE + digit) {
422 return null;
423 }
424 accum -= digit;
425 }
426
427 if (negative) {
428 return accum;
429 } else if (accum == Long.MIN_VALUE) {
430 return null;
431 } else {
432 return -accum;
433 }
434 }
435
436 private static final class LongConverter extends Converter<String, Long> implements Serializable {
437 static final LongConverter INSTANCE = new LongConverter();
438
439 @Override
440 protected Long doForward(String value) {
441 return Long.decode(value);
442 }
443
444 @Override
445 protected String doBackward(Long value) {
446 return value.toString();
447 }
448
449 @Override
450 public String toString() {
451 return "Longs.stringConverter()";
452 }
453
454 private Object readResolve() {
455 return INSTANCE;
456 }
457
458 private static final long serialVersionUID = 1;
459 }
460
461 /**
462 * Returns a serializable converter object that converts between strings and longs using {@link
463 * Long#decode} and {@link Long#toString()}. The returned converter throws {@link
464 * NumberFormatException} if the input string is invalid.
465 *
466 * <p><b>Warning:</b> please see {@link Long#decode} to understand exactly how strings are parsed.
467 * For example, the string {@code "0123"} is treated as <i>octal</i> and converted to the value
468 * {@code 83L}.
469 *
470 * @since 16.0
471 */
472 @Beta
473 public static Converter<String, Long> stringConverter() {
474 return LongConverter.INSTANCE;
475 }
476
477 /**
478 * Returns an array containing the same values as {@code array}, but guaranteed to be of a
479 * specified minimum length. If {@code array} already has a length of at least {@code minLength},
480 * it is returned directly. Otherwise, a new array of size {@code minLength + padding} is
481 * returned, containing the values of {@code array}, and zeroes in the remaining places.
482 *
483 * @param array the source array
484 * @param minLength the minimum length the returned array must guarantee
485 * @param padding an extra amount to "grow" the array by if growth is necessary
486 * @throws IllegalArgumentException if {@code minLength} or {@code padding} is negative
487 * @return an array containing the values of {@code array}, with guaranteed minimum length {@code
488 * minLength}
489 */
490 public static long[] ensureCapacity(long[] array, int minLength, int padding) {
491 checkArgument(minLength >= 0, "Invalid minLength: %s", minLength);
492 checkArgument(padding >= 0, "Invalid padding: %s", padding);
493 return (array.length < minLength) ? Arrays.copyOf(array, minLength + padding) : array;
494 }
495
496 /**
497 * Returns a string containing the supplied {@code long} values separated by {@code separator}.
498 * For example, {@code join("-", 1L, 2L, 3L)} returns the string {@code "1-2-3"}.
499 *
500 * @param separator the text that should appear between consecutive values in the resulting string
501 * (but not at the start or end)
502 * @param array an array of {@code long} values, possibly empty
503 */
504 public static String join(String separator, long... array) {
505 checkNotNull(separator);
506 if (array.length == 0) {
507 return "";
508 }
509
510 // For pre-sizing a builder, just get the right order of magnitude
511 StringBuilder builder = new StringBuilder(array.length * 10);
512 builder.append(array[0]);
513 for (int i = 1; i < array.length; i++) {
514 builder.append(separator).append(array[i]);
515 }
516 return builder.toString();
517 }
518
519 /**
520 * Returns a comparator that compares two {@code long} arrays <a
521 * href="http://en.wikipedia.org/wiki/Lexicographical_order">lexicographically</a>. That is, it
522 * compares, using {@link #compare(long, long)}), the first pair of values that follow any common
523 * prefix, or when one array is a prefix of the other, treats the shorter array as the lesser. For
524 * example, {@code [] < [1L] < [1L, 2L] < [2L]}.
525 *
526 * <p>The returned comparator is inconsistent with {@link Object#equals(Object)} (since arrays
527 * support only identity equality), but it is consistent with {@link Arrays#equals(long[],
528 * long[])}.
529 *
530 * @since 2.0
531 */
532 public static Comparator<long[]> lexicographicalComparator() {
533 return LexicographicalComparator.INSTANCE;
534 }
535
536 private enum LexicographicalComparator implements Comparator<long[]> {
537 INSTANCE;
538
539 @Override
540 public int compare(long[] left, long[] right) {
541 int minLength = Math.min(left.length, right.length);
542 for (int i = 0; i < minLength; i++) {
543 int result = Longs.compare(left[i], right[i]);
544 if (result != 0) {
545 return result;
546 }
547 }
548 return left.length - right.length;
549 }
550
551 @Override
552 public String toString() {
553 return "Longs.lexicographicalComparator()";
554 }
555 }
556
557 /**
558 * Sorts the elements of {@code array} in descending order.
559 *
560 * @since 23.1
561 */
562 public static void sortDescending(long[] array) {
563 checkNotNull(array);
564 sortDescending(array, 0, array.length);
565 }
566
567 /**
568 * Sorts the elements of {@code array} between {@code fromIndex} inclusive and {@code toIndex}
569 * exclusive in descending order.
570 *
571 * @since 23.1
572 */
573 public static void sortDescending(long[] array, int fromIndex, int toIndex) {
574 checkNotNull(array);
575 checkPositionIndexes(fromIndex, toIndex, array.length);
576 Arrays.sort(array, fromIndex, toIndex);
577 reverse(array, fromIndex, toIndex);
578 }
579
580 /**
581 * Reverses the elements of {@code array}. This is equivalent to {@code
582 * Collections.reverse(Longs.asList(array))}, but is likely to be more efficient.
583 *
584 * @since 23.1
585 */
586 public static void reverse(long[] array) {
587 checkNotNull(array);
588 reverse(array, 0, array.length);
589 }
590
591 /**
592 * Reverses the elements of {@code array} between {@code fromIndex} inclusive and {@code toIndex}
593 * exclusive. This is equivalent to {@code
594 * Collections.reverse(Longs.asList(array).subList(fromIndex, toIndex))}, but is likely to be more
595 * efficient.
596 *
597 * @throws IndexOutOfBoundsException if {@code fromIndex < 0}, {@code toIndex > array.length}, or
598 * {@code toIndex > fromIndex}
599 * @since 23.1
600 */
601 public static void reverse(long[] array, int fromIndex, int toIndex) {
602 checkNotNull(array);
603 checkPositionIndexes(fromIndex, toIndex, array.length);
604 for (int i = fromIndex, j = toIndex - 1; i < j; i++, j--) {
605 long tmp = array[i];
606 array[i] = array[j];
607 array[j] = tmp;
608 }
609 }
610
611 /**
612 * Returns an array containing each value of {@code collection}, converted to a {@code long} value
613 * in the manner of {@link Number#longValue}.
614 *
615 * <p>Elements are copied from the argument collection as if by {@code collection.toArray()}.
616 * Calling this method is as thread-safe as calling that method.
617 *
618 * @param collection a collection of {@code Number} instances
619 * @return an array containing the same values as {@code collection}, in the same order, converted
620 * to primitives
621 * @throws NullPointerException if {@code collection} or any of its elements is null
622 * @since 1.0 (parameter was {@code Collection<Long>} before 12.0)
623 */
624 public static long[] toArray(Collection<? extends Number> collection) {
625 if (collection instanceof LongArrayAsList) {
626 return ((LongArrayAsList) collection).toLongArray();
627 }
628
629 Object[] boxedArray = collection.toArray();
630 int len = boxedArray.length;
631 long[] array = new long[len];
632 for (int i = 0; i < len; i++) {
633 // checkNotNull for GWT (do not optimize)
634 array[i] = ((Number) checkNotNull(boxedArray[i])).longValue();
635 }
636 return array;
637 }
638
639 /**
640 * Returns a fixed-size list backed by the specified array, similar to {@link
641 * Arrays#asList(Object[])}. The list supports {@link List#set(int, Object)}, but any attempt to
642 * set a value to {@code null} will result in a {@link NullPointerException}.
643 *
644 * <p>The returned list maintains the values, but not the identities, of {@code Long} objects
645 * written to or read from it. For example, whether {@code list.get(0) == list.get(0)} is true for
646 * the returned list is unspecified.
647 *
648 * <p><b>Note:</b> when possible, you should represent your data as an {@link ImmutableLongArray}
649 * instead, which has an {@link ImmutableLongArray#asList asList} view.
650 *
651 * @param backingArray the array to back the list
652 * @return a list view of the array
653 */
654 public static List<Long> asList(long... backingArray) {
655 if (backingArray.length == 0) {
656 return Collections.emptyList();
657 }
658 return new LongArrayAsList(backingArray);
659 }
660
661 @GwtCompatible
662 private static class LongArrayAsList extends AbstractList<Long>
663 implements RandomAccess, Serializable {
664 final long[] array;
665 final int start;
666 final int end;
667
668 LongArrayAsList(long[] array) {
669 this(array, 0, array.length);
670 }
671
672 LongArrayAsList(long[] array, int start, int end) {
673 this.array = array;
674 this.start = start;
675 this.end = end;
676 }
677
678 @Override
679 public int size() {
680 return end - start;
681 }
682
683 @Override
684 public boolean isEmpty() {
685 return false;
686 }
687
688 @Override
689 public Long get(int index) {
690 checkElementIndex(index, size());
691 return array[start + index];
692 }
693
694 @Override
695 public Spliterator.OfLong spliterator() {
696 return Spliterators.spliterator(array, start, end, 0);
697 }
698
699 @Override
700 public boolean contains(@CheckForNull Object target) {
701 // Overridden to prevent a ton of boxing
702 return (target instanceof Long) && Longs.indexOf(array, (Long) target, start, end) != -1;
703 }
704
705 @Override
706 public int indexOf(@CheckForNull Object target) {
707 // Overridden to prevent a ton of boxing
708 if (target instanceof Long) {
709 int i = Longs.indexOf(array, (Long) target, start, end);
710 if (i >= 0) {
711 return i - start;
712 }
713 }
714 return -1;
715 }
716
717 @Override
718 public int lastIndexOf(@CheckForNull Object target) {
719 // Overridden to prevent a ton of boxing
720 if (target instanceof Long) {
721 int i = Longs.lastIndexOf(array, (Long) target, start, end);
722 if (i >= 0) {
723 return i - start;
724 }
725 }
726 return -1;
727 }
728
729 @Override
730 public Long set(int index, Long element) {
731 checkElementIndex(index, size());
732 long oldValue = array[start + index];
733 // checkNotNull for GWT (do not optimize)
734 array[start + index] = checkNotNull(element);
735 return oldValue;
736 }
737
738 @Override
739 public List<Long> subList(int fromIndex, int toIndex) {
740 int size = size();
741 checkPositionIndexes(fromIndex, toIndex, size);
742 if (fromIndex == toIndex) {
743 return Collections.emptyList();
744 }
745 return new LongArrayAsList(array, start + fromIndex, start + toIndex);
746 }
747
748 @Override
749 public boolean equals(@CheckForNull Object object) {
750 if (object == this) {
751 return true;
752 }
753 if (object instanceof LongArrayAsList) {
754 LongArrayAsList that = (LongArrayAsList) object;
755 int size = size();
756 if (that.size() != size) {
757 return false;
758 }
759 for (int i = 0; i < size; i++) {
760 if (array[start + i] != that.array[that.start + i]) {
761 return false;
762 }
763 }
764 return true;
765 }
766 return super.equals(object);
767 }
768
769 @Override
770 public int hashCode() {
771 int result = 1;
772 for (int i = start; i < end; i++) {
773 result = 31 * result + Longs.hashCode(array[i]);
774 }
775 return result;
776 }
777
778 @Override
779 public String toString() {
780 StringBuilder builder = new StringBuilder(size() * 10);
781 builder.append('[').append(array[start]);
782 for (int i = start + 1; i < end; i++) {
783 builder.append(", ").append(array[i]);
784 }
785 return builder.append(']').toString();
786 }
787
788 long[] toLongArray() {
789 return Arrays.copyOfRange(array, start, end);
790 }
791
792 private static final long serialVersionUID = 0;
793 }
794 }