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 17 #ifndef ANDROID_HWUI_TINYHASHMAP_H 18 #define ANDROID_HWUI_TINYHASHMAP_H 19 20 #include <utils/BasicHashtable.h> 21 22 namespace android { 23 namespace uirenderer { 24 25 /** 26 * A very simple hash map that doesn't allow duplicate keys, overwriting the older entry. 27 */ 28 template <typename TKey, typename TValue> 29 class TinyHashMap { 30 public: 31 typedef key_value_pair_t<TKey, TValue> TEntry; 32 33 /** 34 * Puts an entry in the hash, removing any existing entry with the same key 35 */ 36 void put(TKey key, TValue value) { 37 hash_t hash = android::hash_type(key); 38 39 ssize_t index = mTable.find(-1, hash, key); 40 if (index != -1) { 41 mTable.removeAt(index); 42 } 43 44 TEntry initEntry(key, value); 45 mTable.add(hash, initEntry); 46 } 47 48 /** 49 * Return true if key is in the map, in which case stores the value in the output ref 50 */ 51 bool get(TKey key, TValue& outValue) { 52 hash_t hash = android::hash_type(key); 53 ssize_t index = mTable.find(-1, hash, key); 54 if (index == -1) { 55 return false; 56 } 57 outValue = mTable.entryAt(index).value; 58 return true; 59 } 60 61 void clear() { mTable.clear(); } 62 63 private: 64 BasicHashtable<TKey, TEntry> mTable; 65 }; 66 67 }; // namespace uirenderer 68 }; // namespace android 69 70 #endif // ANDROID_HWUI_TINYHASHMAP_H 71
