71 lines
1.9 KiB
Java
71 lines
1.9 KiB
Java
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/*
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* Copyright (C) 2021 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package com.android.permission.util;
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import android.annotation.Nullable;
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import java.util.Objects;
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/**
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* Array utilities.
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*/
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public final class ArrayUtils {
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private ArrayUtils() {}
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/**
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* @see java.util.List#contains(Object)
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*/
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public static <T> boolean contains(@Nullable T[] array, T value) {
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return indexOf(array, value) != -1;
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}
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/**
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* Get the first element of an array, or {@code null} if none.
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*
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* @param array the array
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* @param <T> the type of the elements of the array
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* @return first element of an array, or {@code null} if none
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*/
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public static <T> T firstOrNull(@Nullable T[] array) {
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return !isEmpty(array) ? array[0] : null;
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}
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/**
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* @see java.util.List#indexOf(Object)
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*/
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public static <T> int indexOf(@Nullable T[] array, T value) {
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if (array == null) {
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return -1;
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}
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final int length = array.length;
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for (int i = 0; i < length; i++) {
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final T element = array[i];
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if (Objects.equals(element, value)) {
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return i;
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}
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}
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return -1;
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}
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/**
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* @see java.util.List#isEmpty()
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*/
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public static <T> boolean isEmpty(@Nullable T[] array) {
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return array == null || array.length == 0;
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}
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}
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