1 /*
2  * Copyright (C) 2023 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.server.permission.access.immutable
18 
19 import android.util.ArraySet
20 
21 /** Immutable set with index-based access. */
22 sealed class IndexedSet<T>(internal val set: ArraySet<T>) : Immutable<MutableIndexedSet<T>> {
23     val size: Int
24         get() = set.size
25 
isEmptynull26     fun isEmpty(): Boolean = set.isEmpty()
27 
28     operator fun contains(element: T): Boolean = set.contains(element)
29 
30     fun indexOf(element: T): Int = set.indexOf(element)
31 
32     fun elementAt(index: Int): T = set.elementAt(index)
33 
34     override fun toMutable(): MutableIndexedSet<T> = MutableIndexedSet(this)
35 
36     override fun toString(): String = set.toString()
37 }
38 
39 /** Mutable set with index-based access. */
40 class MutableIndexedSet<T>(set: ArraySet<T> = ArraySet()) : IndexedSet<T>(set) {
41     constructor(indexedSet: IndexedSet<T>) : this(ArraySet(indexedSet.set))
42 
43     fun add(element: T): Boolean = set.add(element)
44 
45     fun remove(element: T): Boolean = set.remove(element)
46 
47     fun clear() {
48         set.clear()
49     }
50 
51     fun removeAt(index: Int): T = set.removeAt(index)
52 }
53