1 // Copyright 2013 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef IOS_PUBLIC_CONSUMER_BASE_SUPPORTS_USER_DATA_H_ 6 #define IOS_PUBLIC_CONSUMER_BASE_SUPPORTS_USER_DATA_H_ 7 8 namespace ios { 9 10 class SupportsUserDataInternal; 11 12 // This is a helper for classes that want to allow users to stash random data by 13 // key. At destruction all the objects will be destructed. 14 class SupportsUserData { 15 public: 16 SupportsUserData(); 17 18 // Derive from this class and add your own data members to associate extra 19 // information with this object. Alternatively, add this as a public base 20 // class to any class with a virtual destructor. 21 class Data { 22 public: 23 virtual ~Data() {} 24 }; 25 26 // The user data allows the clients to associate data with this object. 27 // Multiple user data values can be stored under different keys. 28 // This object will TAKE OWNERSHIP of the given data pointer, and will 29 // delete the object if it is changed or the object is destroyed. 30 Data* GetUserData(const void* key) const; 31 void SetUserData(const void* key, Data* data); 32 void RemoveUserData(const void* key); 33 34 // SupportsUserData is not thread-safe, and on debug build will assert it is 35 // only used on one thread. Calling this method allows the caller to hand 36 // the SupportsUserData instance across threads. Use only if you are taking 37 // full control of the synchronization of that handover. 38 void DetachUserDataThread(); 39 40 protected: 41 virtual ~SupportsUserData(); 42 43 private: 44 // Owned by this object and scoped to its lifetime. 45 SupportsUserDataInternal* internal_helper_; 46 }; 47 48 } // namespace ios 49 50 #endif // IOS_PUBLIC_CONSUMER_BASE_SUPPORTS_USER_DATA_H_ 51
