chrome/browser/sessions/session_id.h

   1 // Copyright (c) 2012 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_SESSIONS_SESSION_ID_H_
   6 #define CHROME_BROWSER_SESSIONS_SESSION_ID_H_
   7
   8 #include "base/basictypes.h"
   9
  10 class Browser;
  11
  12 namespace content {
  13 class WebContents;
  14 }
  15
  16 // Uniquely identifies a tab or window for the duration of a session.
  17 class SessionID {
  18  public:
  19   typedef int32 id_type;
  20
  21   SessionID();
  22   ~SessionID() {}
  23
  24   // If the specified WebContents has a SessionTabHelper (probably because it
  25   // was used as the contents of a tab), returns a tab id. This value is
  26   // immutable for a given tab. It will be unique across Chrome within the
  27   // current session, but may be re-used across sessions. Returns -1
  28   // for a NULL WebContents or if the WebContents has no SessionTabHelper.
  29   static id_type IdForTab(const content::WebContents* tab);
  30
  31   // If the specified WebContents has a SessionTabHelper (probably because it
  32   // was used as the contents of a tab), and has ever been attached to a Browser
  33   // window, returns Browser::session_id().id() for that Browser. If the tab is
  34   // being dragged between Browser windows, returns the old window's id value.
  35   // If the WebContents has a SessionTabHelper but has never been attached to a
  36   // Browser window, returns an id value that is different from that of any
  37   // Browser. Returns -1 for a NULL WebContents or if the WebContents has no
  38   // SessionTabHelper.
  39   static id_type IdForWindowContainingTab(const content::WebContents* tab);
  40
  41   // Returns the underlying id.
  42   void set_id(id_type id) { id_ = id; }
  43   id_type id() const { return id_; }
  44
  45  private:
  46   id_type id_;
  47 };
  48
  49 #endif  // CHROME_BROWSER_SESSIONS_SESSION_ID_H_