1 /* 2 * Copyright 2014 Google Inc. All rights reserved. 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 #include "cached_greeter.h" 18 #include "key_value_storage.h" 19 20 class CachedGreeterImpl : public Greeter { 21 private: 22 Greeter* greeter; 23 KeyValueStorage* keyValueStorage; 24 25 public: 26 INJECT(CachedGreeterImpl(Greeter* greeter, KeyValueStorage* keyValueStorage)) 27 : greeter(greeter), keyValueStorage(keyValueStorage) { 28 } 29 30 std::string greet() override { 31 std::string greeting = keyValueStorage->get("greeting"); 32 if (!greeting.empty()) { 33 return greeting; 34 } 35 36 // Not in the cache, we need to compute the greeting. 37 greeting = greeter->greet(); 38 39 // We also add it in the cache so that later calls don't need to call greeter->greet(). 40 keyValueStorage->put("greeting", greeting); 41 42 return greeting; 43 } 44 }; 45 46 fruit::Component<fruit::Annotated<Cached, Greeter>> getCachedGreeterComponent() { 47 return fruit::createComponent() 48 .bind<fruit::Annotated<Cached, Greeter>, CachedGreeterImpl>() 49 .install(getKeyValueStorageComponent) 50 .install(getGreeterComponent); 51 } 52
