chrome/browser/metrics/first_web_contents_profiler.h

   1 // Copyright 2014 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 CHROME_BROWSER_METRICS_FIRST_WEB_CONTENTS_PROFILER_H_
   6 #define CHROME_BROWSER_METRICS_FIRST_WEB_CONTENTS_PROFILER_H_
   7
   8 #include "base/memory/scoped_ptr.h"
   9 #include "content/public/browser/web_contents_observer.h"
  10
  11 namespace content {
  12 class WebContents;
  13 }  // namespace content
  14
  15 // Measures start up performance of the first active web contents.
  16 // This class is declared on all platforms, but only defined on non-Android
  17 // platforms. Android code should not call any non-trivial methods on this
  18 // class.
  19 class FirstWebContentsProfiler : public content::WebContentsObserver {
  20  public:
  21   class Delegate {
  22    public:
  23     // Called by the FirstWebContentsProfiler when it is finished collecting
  24     // metrics. The delegate should take this opportunity to destroy the
  25     // FirstWebContentsProfiler.
  26     virtual void ProfilerFinishedCollectingMetrics() = 0;
  27   };
  28
  29   // Creates a profiler for the active web contents. If there are multiple
  30   // browsers, the first one is chosen. If there are no browsers, returns
  31   // nullptr.
  32   static scoped_ptr<FirstWebContentsProfiler> CreateProfilerForFirstWebContents(
  33       Delegate* delegate);
  34
  35  private:
  36   FirstWebContentsProfiler(content::WebContents* web_contents,
  37                            Delegate* delegate);
  38
  39   // content::WebContentsObserver:
  40   void DidFirstVisuallyNonEmptyPaint() override;
  41   void DocumentOnLoadCompletedInMainFrame() override;
  42   void WebContentsDestroyed() override;
  43
  44   // Whether this instance has finished collecting all of its metrics.
  45   bool IsFinishedCollectingMetrics();
  46
  47   // Informs the delegate that this instance has finished collecting all of its
  48   // metrics.
  49   void FinishedCollectingMetrics();
  50
  51   // Whether the "NonEmptyPaint" metric has been collected. If an attempt is
  52   // made to collect the metric but the attempt fails, this member is set to
  53   // true to prevent this class from sitting around forever attempting to
  54   // collect the metric.
  55   bool collected_paint_metric_;
  56
  57   // Whether the "MainFrameLoad" metric has been collected. If an attempt is
  58   // made to collect the metric but the attempt fails, this member is set to
  59   // true to prevent this class from sitting around forever attempting to
  60   // collect the metric.
  61   bool collected_load_metric_;
  62
  63   // The time at which the process was created.
  64   base::Time process_creation_time_;
  65
  66   // |delegate_| owns |this|.
  67   Delegate* delegate_;
  68
  69   DISALLOW_COPY_AND_ASSIGN(FirstWebContentsProfiler);
  70 };
  71
  72 #endif  // CHROME_BROWSER_METRICS_FIRST_WEB_CONTENTS_PROFILER_H_