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28 #ifndef TALK_BASE_MESSAGEHANDLER_H_
29 #define TALK_BASE_MESSAGEHANDLER_H_
31 #include "talk/base/constructormagic.h"
37 // Messages get dispatched to a MessageHandler
39 class MessageHandler {
41 virtual ~MessageHandler();
42 virtual void OnMessage(Message* msg) = 0;
48 DISALLOW_COPY_AND_ASSIGN(MessageHandler);
51 // Helper class to facilitate executing a functor on a thread.
52 template <class ReturnT, class FunctorT>
53 class FunctorMessageHandler : public MessageHandler {
55 explicit FunctorMessageHandler(const FunctorT& functor)
56 : functor_(functor) {}
57 virtual void OnMessage(Message* msg) {
60 const ReturnT& result() const { return result_; }
67 // Specialization for ReturnT of void.
68 template <class FunctorT>
69 class FunctorMessageHandler<void, FunctorT> : public MessageHandler {
71 explicit FunctorMessageHandler(const FunctorT& functor)
72 : functor_(functor) {}
73 virtual void OnMessage(Message* msg) {
76 void result() const {}
83 } // namespace talk_base
85 #endif // TALK_BASE_MESSAGEHANDLER_H_