diff options
Diffstat (limited to 'libs/hwui/utils')
-rw-r--r-- | libs/hwui/utils/TinyHashMap.h | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/libs/hwui/utils/TinyHashMap.h b/libs/hwui/utils/TinyHashMap.h new file mode 100644 index 0000000..8855140 --- /dev/null +++ b/libs/hwui/utils/TinyHashMap.h @@ -0,0 +1,72 @@ +/* + * Copyright (C) 2013 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#ifndef ANDROID_HWUI_TINYHASHMAP_H +#define ANDROID_HWUI_TINYHASHMAP_H + +#include <utils/BasicHashtable.h> + +namespace android { +namespace uirenderer { + +/** + * A very simple hash map that doesn't allow duplicate keys, overwriting the older entry. + * + * Currently, expects simple keys that are handled by hash_t() + */ +template <typename TKey, typename TValue> +class TinyHashMap { +public: + typedef key_value_pair_t<TKey, TValue> TEntry; + + /** + * Puts an entry in the hash, removing any existing entry with the same key + */ + void put(TKey key, TValue value) { + hash_t hash = hash_t(key); + + ssize_t index = mTable.find(-1, hash, key); + if (index != -1) { + mTable.removeAt(index); + } + + TEntry initEntry(key, value); + mTable.add(hash, initEntry); + } + + /** + * Return true if key is in the map, in which case stores the value in the output ref + */ + bool get(TKey key, TValue& outValue) { + hash_t hash = hash_t(key); + ssize_t index = mTable.find(-1, hash, key); + if (index == -1) { + return false; + } + outValue = mTable.entryAt(index).value; + return true; + } + + void clear() { mTable.clear(); } + +private: + BasicHashtable<TKey, TEntry> mTable; +}; + +}; // namespace uirenderer +}; // namespace android + +#endif // ANDROID_HWUI_TINYHASHMAP_H |