components/test_runner/web_task.h

   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 COMPONENTS_TEST_RUNNER_WEB_TASK_H_
   6 #define COMPONENTS_TEST_RUNNER_WEB_TASK_H_
   7
   8 #include <vector>
   9
  10 #include "base/macros.h"
  11
  12 namespace test_runner {
  13
  14 class WebTaskList;
  15
  16 // WebTask represents a task which can run by WebTestDelegate::postTask() or
  17 // WebTestDelegate::postDelayedTask().
  18 class WebTask {
  19  public:
  20   explicit WebTask(WebTaskList*);
  21   virtual ~WebTask();
  22
  23   // The main code of this task.
  24   // An implementation of run() should return immediately if cancel() was
  25   // called.
  26   virtual void run() = 0;
  27   virtual void cancel() = 0;
  28
  29  protected:
  30   WebTaskList* task_list_;
  31 };
  32
  33 class WebTaskList {
  34  public:
  35   WebTaskList();
  36   ~WebTaskList();
  37   void RegisterTask(WebTask*);
  38   void UnregisterTask(WebTask*);
  39   void RevokeAll();
  40
  41  private:
  42   std::vector<WebTask*> tasks_;
  43
  44   DISALLOW_COPY_AND_ASSIGN(WebTaskList);
  45 };
  46
  47 // A task containing an object pointer of class T. Derived classes should
  48 // override RunIfValid() which in turn can safely invoke methods on the
  49 // object_. The Class T must have "WebTaskList* mutable_task_list()".
  50 template <class T>
  51 class WebMethodTask : public WebTask {
  52  public:
  53   explicit WebMethodTask(T* object)
  54       : WebTask(object->mutable_task_list()), object_(object) {}
  55
  56   virtual ~WebMethodTask() {}
  57
  58   void run() override {
  59     if (object_)
  60       RunIfValid();
  61   }
  62
  63   void cancel() override {
  64     object_ = 0;
  65     task_list_->UnregisterTask(this);
  66     task_list_ = 0;
  67   }
  68
  69   virtual void RunIfValid() = 0;
  70
  71  protected:
  72   T* object_;
  73 };
  74
  75 }  // namespace test_runner
  76
  77 #endif  // COMPONENTS_TEST_RUNNER_WEB_TASK_H_