/* * Copyright (C) 2014 The Android Open Source Project * * 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 android.hardware.camera2.utils; import android.util.Log; import java.util.ArrayList; import java.util.List; import java.util.Objects; /** * Various assortment of array utilities. */ public class ArrayUtils { private static final String TAG = "ArrayUtils"; private static final boolean DEBUG = false; /** Return the index of {@code needle} in the {@code array}, or else {@code -1} */ public static int getArrayIndex(T[] array, T needle) { if (array == null) { return -1; } int index = 0; for (T elem : array) { if (Objects.equals(elem, needle)) { return index; } index++; } return -1; } /** Return the index of {@code needle} in the {@code array}, or else {@code -1} */ public static int getArrayIndex(int[] array, int needle) { if (array == null) { return -1; } for (int i = 0; i < array.length; ++i) { if (array[i] == needle) { return i; } } return -1; } /** * Create an {@code int[]} from the {@code List<>} by using {@code convertFrom} and * {@code convertTo} as a one-to-one map (via the index). * *

Strings not appearing in {@code convertFrom} are ignored (with a logged warning); * strings appearing in {@code convertFrom} but not {@code convertTo} are silently * dropped.

* * @param list Source list of strings * @param convertFrom Conversion list of strings * @param convertTo Conversion list of ints * @return An array of ints where the values correspond to the ones in {@code convertTo} * or {@code null} if {@code list} was {@code null} */ public static int[] convertStringListToIntArray( List list, String[] convertFrom, int[] convertTo) { if (list == null) { return null; } List convertedList = convertStringListToIntList(list, convertFrom, convertTo); int[] returnArray = new int[convertedList.size()]; for (int i = 0; i < returnArray.length; ++i) { returnArray[i] = convertedList.get(i); } return returnArray; } /** * Create an {@code List} from the {@code List<>} by using {@code convertFrom} and * {@code convertTo} as a one-to-one map (via the index). * *

Strings not appearing in {@code convertFrom} are ignored (with a logged warning); * strings appearing in {@code convertFrom} but not {@code convertTo} are silently * dropped.

* * @param list Source list of strings * @param convertFrom Conversion list of strings * @param convertTo Conversion list of ints * @return A list of ints where the values correspond to the ones in {@code convertTo} * or {@code null} if {@code list} was {@code null} */ public static List convertStringListToIntList( List list, String[] convertFrom, int[] convertTo) { if (list == null) { return null; } List convertedList = new ArrayList<>(list.size()); for (String str : list) { int strIndex = getArrayIndex(convertFrom, str); // Guard against unexpected values if (strIndex < 0) { if (DEBUG) Log.v(TAG, "Ignoring invalid value " + str); continue; } // Ignore values we can't map into (intentional) if (strIndex < convertTo.length) { convertedList.add(convertTo[strIndex]); } } return convertedList; } /** * Convert the list of integers in {@code list} to an {@code int} array. * *

Every element in {@code list} must be non-{@code null}.

* * @param list a list of non-{@code null} integers * * @return a new int array containing all the elements from {@code list} * * @throws NullPointerException if any of the elements in {@code list} were {@code null} */ public static int[] toIntArray(List list) { if (list == null) { return null; } int[] arr = new int[list.size()]; int i = 0; for (int elem : list) { arr[i] = elem; i++; } return arr; } /** * Returns true if the given {@code array} contains the given element. * * @param array {@code array} to check for {@code elem} * @param elem {@code elem} to test for * @return {@code true} if the given element is contained */ public static boolean contains(int[] array, int elem) { return getArrayIndex(array, elem) != -1; } /** * Returns true if the given {@code array} contains the given element. * * @param array {@code array} to check for {@code elem} * @param elem {@code elem} to test for * @return {@code true} if the given element is contained */ public static boolean contains(T[] array, T elem) { return getArrayIndex(array, elem) != -1; } private ArrayUtils() { throw new AssertionError(); } }