1/*
2 * Copyright (C) 2013 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
17package android.util;
18
19import java.util.ArrayList;
20import java.util.Collections;
21
22public class SparseArray<E> {
23    private final ArrayList<Integer> mKeys;
24    private final ArrayList<E> mValues;
25
26    public SparseArray() {
27        this(10);
28    }
29
30    public SparseArray(final int initialCapacity) {
31        mKeys = new ArrayList<>(initialCapacity);
32        mValues = new ArrayList<>(initialCapacity);
33    }
34
35    public int size() {
36        return mKeys.size();
37    }
38
39    public void clear() {
40        mKeys.clear();
41        mValues.clear();
42    }
43
44    public void put(final int key, final E value) {
45        final int index = Collections.binarySearch(mKeys, key);
46        if (index >= 0) {
47            mValues.set(index, value);
48            return;
49        }
50        final int insertIndex = ~index;
51        mKeys.add(insertIndex, key);
52        mValues.add(insertIndex, value);
53    }
54
55    public E get(final int key) {
56        return get(key, null);
57    }
58
59    public E get(final int key, final E valueIfKeyNotFound) {
60        final int index = Collections.binarySearch(mKeys, key);
61        if (index >= 0) {
62            return mValues.get(index);
63        }
64        return valueIfKeyNotFound;
65    }
66
67    public int indexOfKey(final int key) {
68        return mKeys.indexOf(key);
69    }
70
71    public int indexOfValue(final E value) {
72        return mValues.indexOf(value);
73    }
74
75    public int keyAt(final int index) {
76        return mKeys.get(index);
77    }
78
79    public E valueAt(final int index) {
80        return mValues.get(index);
81    }
82}
83