chrome/browser/prerender/prerender_history.h

   1 // Copyright (c) 2011 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_PRERENDER_PRERENDER_HISTORY_H_
   6 #define CHROME_BROWSER_PRERENDER_PRERENDER_HISTORY_H_
   7
   8 #include <list>
   9
  10 #include "base/threading/non_thread_safe.h"
  11 #include "base/time/time.h"
  12 #include "chrome/browser/prerender/prerender_final_status.h"
  13 #include "chrome/browser/prerender/prerender_origin.h"
  14 #include "url/gurl.h"
  15
  16 namespace base {
  17 class Value;
  18 }
  19
  20 namespace prerender {
  21
  22 // PrerenderHistory maintains a per-session history of prerendered pages
  23 // and their final dispositions. It has a fixed maximum capacity, and old
  24 // items in history will be removed when the capacity is reached.
  25 class PrerenderHistory : public base::NonThreadSafe {
  26  public:
  27   // Entry is an individual entry in the history list. It corresponds to a
  28   // specific prerendered page.
  29   struct Entry {
  30     Entry() : final_status(FINAL_STATUS_MAX), origin(ORIGIN_MAX) {}
  31
  32     Entry(const GURL& url_arg,
  33           FinalStatus final_status_arg,
  34           Origin origin_arg,
  35           base::Time end_time_arg)
  36         : url(url_arg), final_status(final_status_arg),
  37           origin(origin_arg),
  38           end_time(end_time_arg) {
  39     }
  40
  41     // The URL which was prerendered. This should be the URL included in the
  42     // <link rel="prerender"> tag, and not any URLs which it may have redirected
  43     // to.
  44     GURL url;
  45
  46     // The FinalStatus describing whether the prerendered page was used or why
  47     // it was cancelled.
  48     FinalStatus final_status;
  49
  50     // The Origin describing where the prerender originated from.
  51     Origin origin;
  52
  53     // Time the PrerenderContents was destroyed.
  54     base::Time end_time;
  55   };
  56
  57   // Creates a history with capacity for |max_items| entries.
  58   explicit PrerenderHistory(size_t max_items);
  59   ~PrerenderHistory();
  60
  61   // Adds |entry| to the history. If at capacity, the oldest entry is dropped.
  62   void AddEntry(const Entry& entry);
  63
  64   // Deletes all history entries.
  65   void Clear();
  66
  67   // Retrieves the entries as a value which can be displayed.
  68   base::Value* GetEntriesAsValue() const;
  69
  70  private:
  71   std::list<Entry> entries_;
  72   size_t max_items_;
  73
  74   DISALLOW_COPY_AND_ASSIGN(PrerenderHistory);
  75 };
  76
  77 }
  78 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_HISTORY_H_