/* * This source is part of the * _____ ___ ____ * __ / / _ \/ _ | / __/___ _______ _ * / // / , _/ __ |/ _/_/ _ \/ __/ _ `/ * \___/_/|_/_/ |_/_/ (_)___/_/ \_, / * /___/ * repository. * * Copyright (C) 2013 Benoit 'BoD' Lubek (BoD@JRAF.org) * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.jraf.android.util.collection; import java.util.ArrayList; import java.util.Collection; import java.util.Collections; import java.util.Comparator; import java.util.LinkedHashMap; import java.util.LinkedList; import java.util.List; import java.util.Map; public class CollectionUtil { /** * Converts an array of {@code int} into a {@link List} of {@link Integer}. * * @param intArray The array to convert. * @return The newly created {@link List}. */ public static List<Integer> asList(int[] intArray) { List<Integer> res = new ArrayList<Integer>(intArray.length); for (int i : intArray) { res.add(i); } return res; } /** * Converts an array of {@code long} into a {@link List} of {@link Long}. * * @param longArray The array to convert. * @return The newly created {@link List}. */ public static List<Long> asList(long[] longArray) { List<Long> res = new ArrayList<Long>(longArray.length); for (long i : longArray) { res.add(i); } return res; } /** * Converts an array of {@code int} into an array of {@link Integer}. * * @param value The array to convert. * @return The newly created array. */ public static Integer[] wrap(int[] value) { if (value == null) return null; Integer[] res = new Integer[value.length]; for (int i = 0; i < value.length; i++) { res[i] = Integer.valueOf(value[i]); } return res; } /** * Converts an array of {@link Integer} into an array of {@code int}. * * @param value The array to convert. * @return The newly created array. */ public static int[] unwrap(Integer[] value) { if (value == null) return null; int[] res = new int[value.length]; for (int i = 0; i < value.length; i++) { res[i] = value[i]; } return res; } /** * Converts a collection of {@link Integer} into an array of {@code int}. * * @param value The collection to convert. * @return The newly created array. */ public static int[] unwrapInt(Collection<Integer> value) { if (value == null) return null; return unwrap(value.toArray(new Integer[value.size()])); } /** * Converts an array of {@code long} into an array of {@link Long}. * * @param value The array to convert. * @return The newly created array. */ public static Long[] wrap(long[] value) { if (value == null) return null; Long[] res = new Long[value.length]; for (int i = 0; i < value.length; i++) { res[i] = Long.valueOf(value[i]); } return res; } /** * Converts an array of {@link Long} into an array of {@code long}. * * @param value The array to convert. * @return The newly created array. */ public static long[] unwrap(Long[] value) { if (value == null) return null; long[] res = new long[value.length]; for (int i = 0; i < value.length; i++) { res[i] = value[i]; } return res; } /** * Converts a collection of {@link Long} into an array of {@code long}. * * @param value The collection to convert. * @return The newly created array. */ public static long[] unwrapLong(Collection<Long> value) { if (value == null) return null; return unwrap(value.toArray(new Long[value.size()])); } /** * Converts an array of {@code double} into an array of {@link Double}. * * @param value The array to convert. * @return The newly created array. */ public static Double[] wrap(double[] value) { if (value == null) return null; Double[] res = new Double[value.length]; for (int i = 0; i < value.length; i++) { res[i] = Double.valueOf(value[i]); } return res; } /** * Converts an array of {@link Double} into an array of {@code double}. * * @param value The array to convert. * @return The newly created array. */ public static double[] unwrap(Double[] value) { if (value == null) return null; double[] res = new double[value.length]; for (int i = 0; i < value.length; i++) { res[i] = value[i]; } return res; } /** * Converts a collection of {@link Double} into an array of {@code double}. * * @param value The collection to convert. * @return The newly created array. */ public static double[] unwrapDouble(Collection<Double> value) { if (value == null) return null; return unwrap(value.toArray(new Double[value.size()])); } /** * Converts an array of {@code float} into an array of {@link Float}. * * @param value The array to convert. * @return The newly created array. */ public static Float[] wrap(float[] value) { if (value == null) return null; Float[] res = new Float[value.length]; for (int i = 0; i < value.length; i++) { res[i] = Float.valueOf(value[i]); } return res; } /** * Converts an array of {@link Float} into an array of {@code float}. * * @param value The array to convert. * @return The newly created array. */ public static float[] unwrap(Float[] value) { if (value == null) return null; float[] res = new float[value.length]; for (int i = 0; i < value.length; i++) { res[i] = value[i]; } return res; } /** * Converts a collection of {@link Float} into an array of {@code float}. * * @param value The collection to convert. * @return The newly created array. */ public static float[] unwrapFloat(Collection<Float> value) { if (value == null) return null; return unwrap(value.toArray(new Float[value.size()])); } /** * Returns a new {@link Map} where the values are sorted according to the given comparator (or using the natural order if the comparator is {@code null}). * * @param map The original map of which to get a sorted version. * @param comparator The comparator to use, or {@code null} to use the natural order. */ public static <K, V extends Comparable<? super V>> Map<K, V> getMapSortedByValue(Map<K, V> map, final Comparator<V> comparator) { List<Map.Entry<K, V>> list = new LinkedList<Map.Entry<K, V>>(map.entrySet()); Collections.sort(list, new Comparator<Map.Entry<K, V>>() { @Override public int compare(Map.Entry<K, V> o1, Map.Entry<K, V> o2) { if (comparator == null) { return o1.getValue().compareTo(o2.getValue()); } return comparator.compare(o1.getValue(), o2.getValue()); } }); Map<K, V> result = new LinkedHashMap<K, V>(); for (Map.Entry<K, V> entry : list) { result.put(entry.getKey(), entry.getValue()); } return result; } }