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