task_observer.h (1095B)
1 // Copyright 2018 The Chromium Authors 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 BASE_TASK_TASK_OBSERVER_H_ 6 #define BASE_TASK_TASK_OBSERVER_H_ 7 8 #include "base/base_export.h" 9 #include "base/pending_task.h" 10 11 namespace base { 12 13 // A TaskObserver is an object that receives notifications about tasks being 14 // processed on the thread it's associated with. 15 // 16 // NOTE: A TaskObserver implementation should be extremely fast! 17 18 class BASE_EXPORT TaskObserver { 19 public: 20 // This method is called before processing a task. 21 // |was_blocked_or_low_priority| indicates if the task was at some point in a 22 // queue that was blocked or less important than "normal". 23 virtual void WillProcessTask(const PendingTask& pending_task, 24 bool was_blocked_or_low_priority) = 0; 25 26 // This method is called after processing a task. 27 virtual void DidProcessTask(const PendingTask& pending_task) = 0; 28 29 protected: 30 virtual ~TaskObserver() = default; 31 }; 32 33 } // namespace base 34 35 #endif // BASE_TASK_TASK_OBSERVER_H_