1 /* 2 * Copyright (C) 2015 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 #pragma once 18 19 class AudioPolicyManagerInterface; 20 21 namespace android 22 { 23 namespace audio_policy 24 { 25 26 class Engine; 27 28 class EngineInstance 29 { 30 protected: 31 EngineInstance(); 32 33 public: 34 virtual ~EngineInstance(); 35 36 /** 37 * Get Audio Policy Engine instance. 38 * 39 * @return pointer to Route Manager Instance object. 40 */ 41 static EngineInstance *getInstance(); 42 43 /** 44 * Interface query. 45 * The first client of an interface of the policy engine will start the singleton. 46 * 47 * @tparam RequestedInterface: interface that the client is wishing to retrieve. 48 * 49 * @return interface handle. 50 */ 51 template <class RequestedInterface> 52 RequestedInterface *queryInterface() const; 53 54 protected: 55 /** 56 * Get Audio Policy Engine instance. 57 * 58 * @return Audio Policy Engine singleton. 59 */ 60 Engine *getEngine() const; 61 62 private: 63 /* Copy facilities are put private to disable copy. */ 64 EngineInstance(const EngineInstance &object); 65 EngineInstance &operator=(const EngineInstance &object); 66 }; 67 68 /** 69 * Limit template instantation to supported type interfaces. 70 * Compile time error will claim if invalid interface is requested. 71 */ 72 template <> 73 AudioPolicyManagerInterface *EngineInstance::queryInterface() const; 74 75 } // namespace audio_policy 76 } // namespace android 77
