1bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor/* 21d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Copyright (C) 2008 The Guava Authors 3bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 4bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Licensed under the Apache License, Version 2.0 (the "License"); 5bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * you may not use this file except in compliance with the License. 6bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * You may obtain a copy of the License at 7bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 8bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * http://www.apache.org/licenses/LICENSE-2.0 9bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 10bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Unless required by applicable law or agreed to in writing, software 11bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * distributed under the License is distributed on an "AS IS" BASIS, 12bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * See the License for the specific language governing permissions and 14bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * limitations under the License. 15bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 16bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 17bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnorpackage com.google.common.primitives; 18bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 191d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport static com.google.common.base.Preconditions.checkArgument; 201d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport static com.google.common.base.Preconditions.checkElementIndex; 211d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport static com.google.common.base.Preconditions.checkNotNull; 221d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport static com.google.common.base.Preconditions.checkPositionIndexes; 231d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 24bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnorimport com.google.common.annotations.GwtCompatible; 25bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 26bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnorimport java.io.Serializable; 27bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnorimport java.util.AbstractList; 28bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnorimport java.util.Collection; 29bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnorimport java.util.Collections; 30bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnorimport java.util.Comparator; 31bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnorimport java.util.List; 32bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnorimport java.util.RandomAccess; 33bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 34bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor/** 35bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Static utility methods pertaining to {@code int} primitives, that are not 36bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * already found in either {@link Integer} or {@link Arrays}. 37bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 38bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @author Kevin Bourrillion 391d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * @since 1.0 40bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 411d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert@GwtCompatible(emulated = true) 42bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnorpublic final class Ints { 43bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor private Ints() {} 44bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 45bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 46bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * The number of bytes required to represent a primitive {@code int} 47bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * value. 48bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 49bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static final int BYTES = Integer.SIZE / Byte.SIZE; 50bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 51bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 521d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * The largest power of two that can be represented as an {@code int}. 531d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 541d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * @since 10.0 551d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 561d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public static final int MAX_POWER_OF_TWO = 1 << (Integer.SIZE - 2); 571d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 581d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert /** 59bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Returns a hash code for {@code value}; equal to the result of invoking 60bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * {@code ((Integer) value).hashCode()}. 61bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 62bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param value a primitive {@code int} value 63bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @return a hash code for the value 64bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 65bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static int hashCode(int value) { 66bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return value; 67bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 68bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 69bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 70bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Returns the {@code int} value that is equal to {@code value}, if possible. 71bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 72bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param value any value in the range of the {@code int} type 73bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @return the {@code int} value that equals {@code value} 74bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @throws IllegalArgumentException if {@code value} is greater than {@link 75bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Integer#MAX_VALUE} or less than {@link Integer#MIN_VALUE} 76bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 77bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static int checkedCast(long value) { 78bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int result = (int) value; 79bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor checkArgument(result == value, "Out of range: %s", value); 80bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return result; 81bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 82bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 83bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 84bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Returns the {@code int} nearest in value to {@code value}. 85bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 86bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param value any {@code long} value 87bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @return the same value cast to {@code int} if it is in the range of the 88bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * {@code int} type, {@link Integer#MAX_VALUE} if it is too large, 89bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * or {@link Integer#MIN_VALUE} if it is too small 90bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 91bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static int saturatedCast(long value) { 92bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (value > Integer.MAX_VALUE) { 93bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return Integer.MAX_VALUE; 94bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 95bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (value < Integer.MIN_VALUE) { 96bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return Integer.MIN_VALUE; 97bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 98bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return (int) value; 99bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 100bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 101bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 102bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Compares the two specified {@code int} values. The sign of the value 103bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * returned is the same as that of {@code ((Integer) a).compareTo(b)}. 104bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 105bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param a the first {@code int} to compare 106bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param b the second {@code int} to compare 107bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @return a negative value if {@code a} is less than {@code b}; a positive 108bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * value if {@code a} is greater than {@code b}; or zero if they are equal 109bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 110bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static int compare(int a, int b) { 111bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return (a < b) ? -1 : ((a > b) ? 1 : 0); 112bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 113bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 114bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 115bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Returns {@code true} if {@code target} is present as an element anywhere in 116bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * {@code array}. 117bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 118bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param array an array of {@code int} values, possibly empty 119bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param target a primitive {@code int} value 120bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @return {@code true} if {@code array[i] == target} for some value of {@code 121bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * i} 122bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 123bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static boolean contains(int[] array, int target) { 124bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor for (int value : array) { 125bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (value == target) { 126bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return true; 127bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 128bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 129bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return false; 130bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 131bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 132bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 133bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Returns the index of the first appearance of the value {@code target} in 134bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * {@code array}. 135bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 136bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param array an array of {@code int} values, possibly empty 137bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param target a primitive {@code int} value 138bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @return the least index {@code i} for which {@code array[i] == target}, or 139bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * {@code -1} if no such index exists. 140bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 141bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static int indexOf(int[] array, int target) { 142bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return indexOf(array, target, 0, array.length); 143bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 144bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 1451d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert // TODO(kevinb): consider making this public 146bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor private static int indexOf( 147bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int[] array, int target, int start, int end) { 148bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor for (int i = start; i < end; i++) { 149bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (array[i] == target) { 150bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return i; 151bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 152bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 153bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return -1; 154bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 155bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 156bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 157bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Returns the start position of the first occurrence of the specified {@code 158bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * target} within {@code array}, or {@code -1} if there is no such occurrence. 159bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 160bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * <p>More formally, returns the lowest index {@code i} such that {@code 161bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * java.util.Arrays.copyOfRange(array, i, i + target.length)} contains exactly 162bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * the same elements as {@code target}. 163bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 164bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param array the array to search for the sequence {@code target} 165bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param target the array to search for as a sub-sequence of {@code array} 166bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 167bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static int indexOf(int[] array, int[] target) { 168bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor checkNotNull(array, "array"); 169bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor checkNotNull(target, "target"); 170bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (target.length == 0) { 171bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return 0; 172bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 173bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 174bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor outer: 175bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor for (int i = 0; i < array.length - target.length + 1; i++) { 176bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor for (int j = 0; j < target.length; j++) { 177bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (array[i + j] != target[j]) { 178bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor continue outer; 179bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 180bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 181bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return i; 182bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 183bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return -1; 184bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 185bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 186bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 187bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Returns the index of the last appearance of the value {@code target} in 188bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * {@code array}. 189bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 190bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param array an array of {@code int} values, possibly empty 191bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param target a primitive {@code int} value 192bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @return the greatest index {@code i} for which {@code array[i] == target}, 193bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * or {@code -1} if no such index exists. 194bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 195bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static int lastIndexOf(int[] array, int target) { 196bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return lastIndexOf(array, target, 0, array.length); 197bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 198bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 1991d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert // TODO(kevinb): consider making this public 200bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor private static int lastIndexOf( 201bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int[] array, int target, int start, int end) { 202bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor for (int i = end - 1; i >= start; i--) { 203bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (array[i] == target) { 204bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return i; 205bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 206bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 207bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return -1; 208bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 209bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 210bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 211bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Returns the least value present in {@code array}. 212bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 213bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param array a <i>nonempty</i> array of {@code int} values 214bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @return the value present in {@code array} that is less than or equal to 215bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * every other value in the array 216bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @throws IllegalArgumentException if {@code array} is empty 217bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 218bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static int min(int... array) { 219bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor checkArgument(array.length > 0); 220bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int min = array[0]; 221bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor for (int i = 1; i < array.length; i++) { 222bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (array[i] < min) { 223bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor min = array[i]; 224bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 225bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 226bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return min; 227bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 228bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 229bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 230bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Returns the greatest value present in {@code array}. 231bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 232bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param array a <i>nonempty</i> array of {@code int} values 233bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @return the value present in {@code array} that is greater than or equal to 234bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * every other value in the array 235bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @throws IllegalArgumentException if {@code array} is empty 236bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 237bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static int max(int... array) { 238bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor checkArgument(array.length > 0); 239bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int max = array[0]; 240bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor for (int i = 1; i < array.length; i++) { 241bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (array[i] > max) { 242bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor max = array[i]; 243bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 244bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 245bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return max; 246bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 247bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 248bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 249bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Returns the values from each provided array combined into a single array. 250bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * For example, {@code concat(new int[] {a, b}, new int[] {}, new 251bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * int[] {c}} returns the array {@code {a, b, c}}. 252bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 253bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param arrays zero or more {@code int} arrays 254bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @return a single array containing all the values from the source arrays, in 255bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * order 256bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 257bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static int[] concat(int[]... arrays) { 258bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int length = 0; 259bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor for (int[] array : arrays) { 260bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor length += array.length; 261bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 262bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int[] result = new int[length]; 263bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int pos = 0; 264bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor for (int[] array : arrays) { 265bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor System.arraycopy(array, 0, result, pos, array.length); 266bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor pos += array.length; 267bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 268bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return result; 269bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 270bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 271bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 272bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Returns an array containing the same values as {@code array}, but 273bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * guaranteed to be of a specified minimum length. If {@code array} already 274bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * has a length of at least {@code minLength}, it is returned directly. 275bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Otherwise, a new array of size {@code minLength + padding} is returned, 276bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * containing the values of {@code array}, and zeroes in the remaining places. 277bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 278bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param array the source array 279bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param minLength the minimum length the returned array must guarantee 280bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param padding an extra amount to "grow" the array by if growth is 281bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * necessary 282bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @throws IllegalArgumentException if {@code minLength} or {@code padding} is 283bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * negative 284bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @return an array containing the values of {@code array}, with guaranteed 285bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * minimum length {@code minLength} 286bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 287bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static int[] ensureCapacity( 288bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int[] array, int minLength, int padding) { 289bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor checkArgument(minLength >= 0, "Invalid minLength: %s", minLength); 290bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor checkArgument(padding >= 0, "Invalid padding: %s", padding); 291bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return (array.length < minLength) 292bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor ? copyOf(array, minLength + padding) 293bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor : array; 294bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 295bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 296bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor // Arrays.copyOf() requires Java 6 297bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor private static int[] copyOf(int[] original, int length) { 298bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int[] copy = new int[length]; 299bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor System.arraycopy(original, 0, copy, 0, Math.min(original.length, length)); 300bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return copy; 301bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 302bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 303bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 304bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Returns a string containing the supplied {@code int} values separated 305bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * by {@code separator}. For example, {@code join("-", 1, 2, 3)} returns 306bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * the string {@code "1-2-3"}. 307bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 308bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param separator the text that should appear between consecutive values in 309bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * the resulting string (but not at the start or end) 310bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param array an array of {@code int} values, possibly empty 311bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 312bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static String join(String separator, int... array) { 313bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor checkNotNull(separator); 314bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (array.length == 0) { 315bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return ""; 316bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 317bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 318bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor // For pre-sizing a builder, just get the right order of magnitude 319bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor StringBuilder builder = new StringBuilder(array.length * 5); 320bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor builder.append(array[0]); 321bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor for (int i = 1; i < array.length; i++) { 322bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor builder.append(separator).append(array[i]); 323bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 324bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return builder.toString(); 325bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 326bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 327bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 328bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Returns a comparator that compares two {@code int} arrays 329bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * lexicographically. That is, it compares, using {@link 330bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * #compare(int, int)}), the first pair of values that follow any 331bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * common prefix, or when one array is a prefix of the other, treats the 332bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * shorter array as the lesser. For example, {@code [] < [1] < [1, 2] < [2]}. 333bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 334bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * <p>The returned comparator is inconsistent with {@link 335bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Object#equals(Object)} (since arrays support only identity equality), but 336bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * it is consistent with {@link Arrays#equals(int[], int[])}. 337bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 338bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @see <a href="http://en.wikipedia.org/wiki/Lexicographical_order"> 3391d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Lexicographical order article at Wikipedia</a> 3401d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * @since 2.0 341bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 342bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static Comparator<int[]> lexicographicalComparator() { 343bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return LexicographicalComparator.INSTANCE; 344bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 345bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 346bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor private enum LexicographicalComparator implements Comparator<int[]> { 347bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor INSTANCE; 348bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 3491d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 350bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public int compare(int[] left, int[] right) { 351bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int minLength = Math.min(left.length, right.length); 352bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor for (int i = 0; i < minLength; i++) { 353bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int result = Ints.compare(left[i], right[i]); 354bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (result != 0) { 355bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return result; 356bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 357bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 358bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return left.length - right.length; 359bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 360bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 361bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 362bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 363bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Copies a collection of {@code Integer} instances into a new array of 364bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * primitive {@code int} values. 365bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 366bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * <p>Elements are copied from the argument collection as if by {@code 367bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * collection.toArray()}. Calling this method is as thread-safe as calling 368bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * that method. 369bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 370bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param collection a collection of {@code Integer} objects 371bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @return an array containing the same values as {@code collection}, in the 372bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * same order, converted to primitives 373bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @throws NullPointerException if {@code collection} or any of its elements 374bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * is null 375bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 376bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static int[] toArray(Collection<Integer> collection) { 377bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (collection instanceof IntArrayAsList) { 378bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return ((IntArrayAsList) collection).toIntArray(); 379bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 380bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 381bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor Object[] boxedArray = collection.toArray(); 382bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int len = boxedArray.length; 383bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int[] array = new int[len]; 384bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor for (int i = 0; i < len; i++) { 3851d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert // checkNotNull for GWT (do not optimize) 3861d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert array[i] = (Integer) checkNotNull(boxedArray[i]); 387bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 388bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return array; 389bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 390bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 391bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 392bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Returns a fixed-size list backed by the specified array, similar to {@link 393bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Arrays#asList(Object[])}. The list supports {@link List#set(int, Object)}, 394bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * but any attempt to set a value to {@code null} will result in a {@link 395bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * NullPointerException}. 396bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 397bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * <p>The returned list maintains the values, but not the identities, of 398bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * {@code Integer} objects written to or read from it. For example, whether 399bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * {@code list.get(0) == list.get(0)} is true for the returned list is 400bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * unspecified. 401bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 402bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @param backingArray the array to back the list 403bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @return a list view of the array 404bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 405bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public static List<Integer> asList(int... backingArray) { 406bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (backingArray.length == 0) { 407bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return Collections.emptyList(); 408bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 409bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return new IntArrayAsList(backingArray); 410bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 411bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 412bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor @GwtCompatible 413bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor private static class IntArrayAsList extends AbstractList<Integer> 414bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor implements RandomAccess, Serializable { 415bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor final int[] array; 416bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor final int start; 417bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor final int end; 418bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 419bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor IntArrayAsList(int[] array) { 420bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor this(array, 0, array.length); 421bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 422bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 423bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor IntArrayAsList(int[] array, int start, int end) { 424bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor this.array = array; 425bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor this.start = start; 426bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor this.end = end; 427bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 428bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 429bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor @Override public int size() { 430bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return end - start; 431bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 432bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 433bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor @Override public boolean isEmpty() { 434bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return false; 435bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 436bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 437bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor @Override public Integer get(int index) { 438bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor checkElementIndex(index, size()); 439bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return array[start + index]; 440bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 441bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 442bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor @Override public boolean contains(Object target) { 443bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor // Overridden to prevent a ton of boxing 444bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return (target instanceof Integer) 445bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor && Ints.indexOf(array, (Integer) target, start, end) != -1; 446bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 447bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 448bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor @Override public int indexOf(Object target) { 449bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor // Overridden to prevent a ton of boxing 450bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (target instanceof Integer) { 451bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int i = Ints.indexOf(array, (Integer) target, start, end); 452bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (i >= 0) { 453bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return i - start; 454bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 455bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 456bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return -1; 457bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 458bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 459bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor @Override public int lastIndexOf(Object target) { 460bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor // Overridden to prevent a ton of boxing 461bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (target instanceof Integer) { 462bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int i = Ints.lastIndexOf(array, (Integer) target, start, end); 463bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (i >= 0) { 464bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return i - start; 465bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 466bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 467bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return -1; 468bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 469bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 470bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor @Override public Integer set(int index, Integer element) { 471bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor checkElementIndex(index, size()); 472bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int oldValue = array[start + index]; 4731d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert array[start + index] = checkNotNull(element); // checkNotNull for GWT (do not optimize) 474bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return oldValue; 475bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 476bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 4771d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override public List<Integer> subList(int fromIndex, int toIndex) { 478bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int size = size(); 479bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor checkPositionIndexes(fromIndex, toIndex, size); 480bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (fromIndex == toIndex) { 481bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return Collections.emptyList(); 482bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 483bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return new IntArrayAsList(array, start + fromIndex, start + toIndex); 484bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 485bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 486bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor @Override public boolean equals(Object object) { 487bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (object == this) { 488bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return true; 489bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 490bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (object instanceof IntArrayAsList) { 491bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor IntArrayAsList that = (IntArrayAsList) object; 492bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int size = size(); 493bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (that.size() != size) { 494bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return false; 495bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 496bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor for (int i = 0; i < size; i++) { 497bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (array[start + i] != that.array[that.start + i]) { 498bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return false; 499bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 500bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 501bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return true; 502bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 503bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return super.equals(object); 504bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 505bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 506bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor @Override public int hashCode() { 507bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int result = 1; 508bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor for (int i = start; i < end; i++) { 509bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor result = 31 * result + Ints.hashCode(array[i]); 510bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 511bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return result; 512bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 513bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 514bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor @Override public String toString() { 515bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor StringBuilder builder = new StringBuilder(size() * 5); 516bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor builder.append('[').append(array[start]); 517bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor for (int i = start + 1; i < end; i++) { 518bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor builder.append(", ").append(array[i]); 519bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 520bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return builder.append(']').toString(); 521bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 522bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 523bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int[] toIntArray() { 524bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor // Arrays.copyOfRange() requires Java 6 525bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int size = size(); 526bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor int[] result = new int[size]; 527bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor System.arraycopy(array, start, result, 0, size); 528bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return result; 529bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 530bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 531bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor private static final long serialVersionUID = 0; 532bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 533bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor} 534