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      1 /*
      2  * Copyright (C) 2018 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 package android.util;
     17 
     18 /**
     19  * A sparse array of ArraySets, which is suitable to hold userid->packages association.
     20  *
     21  * @hide
     22  */
     23 public class SparseSetArray<T> {
     24     private final SparseArray<ArraySet<T>> mData = new SparseArray<>();
     25 
     26     public SparseSetArray() {
     27     }
     28 
     29     /**
     30      * Add a value at index n.
     31      * @return FALSE when the value already existed at the given index, TRUE otherwise.
     32      */
     33     public boolean add(int n, T value) {
     34         ArraySet<T> set = mData.get(n);
     35         if (set == null) {
     36             set = new ArraySet<>();
     37             mData.put(n, set);
     38         }
     39         if (set.contains(value)) {
     40             return true;
     41         }
     42         set.add(value);
     43         return false;
     44     }
     45 
     46     /**
     47      * Removes all mappings from this SparseSetArray.
     48      */
     49     public void clear() {
     50         mData.clear();
     51     }
     52 
     53     /**
     54      * @return whether a value exists at index n.
     55      */
     56     public boolean contains(int n, T value) {
     57         final ArraySet<T> set = mData.get(n);
     58         if (set == null) {
     59             return false;
     60         }
     61         return set.contains(value);
     62     }
     63 
     64     /**
     65      * @return the set of items at index n
     66      */
     67     public ArraySet<T> get(int n) {
     68         return mData.get(n);
     69     }
     70 
     71     /**
     72      * Remove a value from index n.
     73      * @return TRUE when the value existed at the given index and removed, FALSE otherwise.
     74      */
     75     public boolean remove(int n, T value) {
     76         final ArraySet<T> set = mData.get(n);
     77         if (set == null) {
     78             return false;
     79         }
     80         final boolean ret = set.remove(value);
     81         if (set.size() == 0) {
     82             mData.remove(n);
     83         }
     84         return ret;
     85     }
     86 
     87     /**
     88      * Remove all values from index n.
     89      */
     90     public void remove(int n) {
     91         mData.remove(n);
     92     }
     93     public int size() {
     94         return mData.size();
     95     }
     96 
     97     public int keyAt(int index) {
     98         return mData.keyAt(index);
     99     }
    100 
    101     public int sizeAt(int index) {
    102         final ArraySet<T> set = mData.valueAt(index);
    103         if (set == null) {
    104             return 0;
    105         }
    106         return set.size();
    107     }
    108 
    109     public T valueAt(int intIndex, int valueIndex) {
    110         return mData.valueAt(intIndex).valueAt(valueIndex);
    111     }
    112 }
    113