| /* |
| * Copyright (C) 2019 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 com.android.server.wifi.util; |
| |
| import android.annotation.Nullable; |
| |
| import java.util.Collection; |
| import java.util.Objects; |
| |
| /** |
| * Copied over from frameworks/base/core/java/com/android/internal/util/ArrayUtils.java |
| */ |
| public class ArrayUtils { |
| private ArrayUtils() { /* cannot be instantiated */ } |
| |
| /** |
| * Checks if the beginnings of two byte arrays are equal. |
| * |
| * @param array1 the first byte array |
| * @param array2 the second byte array |
| * @param length the number of bytes to check |
| * @return true if they're equal, false otherwise |
| */ |
| public static boolean equals(byte[] array1, byte[] array2, int length) { |
| if (length < 0) { |
| throw new IllegalArgumentException(); |
| } |
| |
| if (array1 == array2) { |
| return true; |
| } |
| if (array1 == null || array2 == null || array1.length < length || array2.length < length) { |
| return false; |
| } |
| for (int i = 0; i < length; i++) { |
| if (array1[i] != array2[i]) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * Checks if given array is null or has zero elements. |
| */ |
| public static boolean isEmpty(@Nullable Collection<?> array) { |
| return array == null || array.isEmpty(); |
| } |
| |
| /** |
| * Checks if given array is null or has zero elements. |
| */ |
| public static <T> boolean isEmpty(@Nullable T[] array) { |
| return array == null || array.length == 0; |
| } |
| |
| /** |
| * Checks if given array is null or has zero elements. |
| */ |
| public static boolean isEmpty(@Nullable int[] array) { |
| return array == null || array.length == 0; |
| } |
| |
| /** |
| * Checks if given array is null or has zero elements. |
| */ |
| public static boolean isEmpty(@Nullable long[] array) { |
| return array == null || array.length == 0; |
| } |
| |
| /** |
| * Checks if given array is null or has zero elements. |
| */ |
| public static boolean isEmpty(@Nullable byte[] array) { |
| return array == null || array.length == 0; |
| } |
| |
| /** |
| * Checks if given array is null or has zero elements. |
| */ |
| public static boolean isEmpty(@Nullable boolean[] array) { |
| return array == null || array.length == 0; |
| } |
| |
| /** |
| * Length of the given array or 0 if it's null. |
| */ |
| public static int size(@Nullable Object[] array) { |
| return array == null ? 0 : array.length; |
| } |
| |
| /** |
| * Length of the given collection or 0 if it's null. |
| */ |
| public static int size(@Nullable Collection<?> collection) { |
| return collection == null ? 0 : collection.size(); |
| } |
| |
| /** |
| * Checks that value is present as at least one of the elements of the array. |
| * |
| * @param array the array to check in |
| * @param value the value to check for |
| * @return true if the value is present in the array |
| */ |
| public static <T> boolean contains(@Nullable T[] array, T value) { |
| return indexOf(array, value) != -1; |
| } |
| |
| /** |
| * Checks that value is present as at least one of the elements of the array. |
| * |
| * @param array the array to check in |
| * @param value the value to check for |
| * @return true if the value is present in the array |
| */ |
| public static boolean contains(@Nullable int[] array, int value) { |
| if (array == null) return false; |
| for (int element : array) { |
| if (element == value) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Checks that value is present as at least one of the elements of the array. |
| * |
| * @param array the array to check in |
| * @param value the value to check for |
| * @return true if the value is present in the array |
| */ |
| public static boolean contains(@Nullable long[] array, long value) { |
| if (array == null) return false; |
| for (long element : array) { |
| if (element == value) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Checks that value is present as at least one of the elements of the array. |
| * |
| * @param array the array to check in |
| * @param value the value to check for |
| * @return true if the value is present in the array |
| */ |
| public static boolean contains(@Nullable char[] array, char value) { |
| if (array == null) return false; |
| for (char element : array) { |
| if (element == value) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Return first index of {@code value} in {@code array}, or {@code -1} if |
| * not found. |
| */ |
| public static <T> int indexOf(@Nullable T[] array, T value) { |
| if (array == null) return -1; |
| for (int i = 0; i < array.length; i++) { |
| if (Objects.equals(array[i], value)) return i; |
| } |
| return -1; |
| } |
| } |
| |