Home | History | Annotate | Download | only in base 
      1 /*
      2  * Copyright (C) 2014 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 ART_LIBARTBASE_BASE_HASH_MAP_H_
     18 #define ART_LIBARTBASE_BASE_HASH_MAP_H_
     19 
     20 #include <utility>
     21 
     22 #include "hash_set.h"
     23 
     24 namespace art {
     25 
     26 template <typename Fn>
     27 class HashMapWrapper {
     28  public:
     29   // Hash function.
     30   template <class Key, class Value>
     31   size_t operator()(const std::pair<Key, Value>& pair) const {
     32     return fn_(pair.first);
     33   }
     34   template <class Key>
     35   size_t operator()(const Key& key) const {
     36     return fn_(key);
     37   }
     38   template <class Key, class Value>
     39   bool operator()(const std::pair<Key, Value>& a, const std::pair<Key, Value>& b) const {
     40     return fn_(a.first, b.first);
     41   }
     42   template <class Key, class Value, class Element>
     43   bool operator()(const std::pair<Key, Value>& a, const Element& element) const {
     44     return fn_(a.first, element);
     45   }
     46 
     47  private:
     48   Fn fn_;
     49 };
     50 
     51 template <class Key, class Value, class EmptyFn,
     52     class HashFn = std::hash<Key>, class Pred = std::equal_to<Key>,
     53     class Alloc = std::allocator<std::pair<Key, Value>>>
     54 class HashMap : public HashSet<std::pair<Key, Value>,
     55                                EmptyFn,
     56                                HashMapWrapper<HashFn>,
     57                                HashMapWrapper<Pred>,
     58                                Alloc> {
     59  private:
     60   using Base = HashSet<std::pair<Key, Value>,
     61                        EmptyFn,
     62                        HashMapWrapper<HashFn>,
     63                        HashMapWrapper<Pred>,
     64                        Alloc>;
     65 
     66  public:
     67   HashMap() : Base() { }
     68   explicit HashMap(const Alloc& alloc)
     69       : Base(alloc) { }
     70 };
     71 
     72 }  // namespace art
     73 
     74 #endif  // ART_LIBARTBASE_BASE_HASH_MAP_H_
     75