third_party/WebKit/public/platform/WebPrerenderingSupport.h

   1 /*
   2  * Copyright (C) 2012 Google Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions are
   6  * met:
   7  *
   8  *     * Redistributions of source code must retain the above copyright
   9  * notice, this list of conditions and the following disclaimer.
  10  *     * Redistributions in binary form must reproduce the above
  11  * copyright notice, this list of conditions and the following disclaimer
  12  * in the documentation and/or other materials provided with the
  13  * distribution.
  14  *     * Neither the name of Google Inc. nor the names of its
  15  * contributors may be used to endorse or promote products derived from
  16  * this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #ifndef WebPrerenderingSupport_h
  32 #define WebPrerenderingSupport_h
  33
  34 #include "WebCommon.h"
  35
  36 namespace blink {
  37
  38 class WebPrerender;
  39
  40 class WebPrerenderingSupport {
  41 public:
  42     BLINK_PLATFORM_EXPORT static void initialize(WebPrerenderingSupport*);
  43     BLINK_PLATFORM_EXPORT static void shutdown();
  44     BLINK_PLATFORM_EXPORT static WebPrerenderingSupport* current();
  45
  46     // A prerender link element is added when it is inserted into a document.
  47     virtual void add(const WebPrerender&) = 0;
  48
  49     // A prerender is canceled when it is removed from a document.
  50     virtual void cancel(const WebPrerender&) = 0;
  51
  52     // A prerender is abandoned when it's navigated away from or suspended in the page cache. This
  53     // is a weaker signal than cancel(), since the launcher hasn't indicated that the prerender isn't
  54     // wanted, and we may end up using it after, for instance, a short redirect chain.
  55     virtual void abandon(const WebPrerender&) = 0;
  56
  57 protected:
  58     WebPrerenderingSupport() { }
  59     virtual ~WebPrerenderingSupport() { }
  60
  61 private:
  62     static WebPrerenderingSupport* s_platform;
  63 };
  64
  65 } // namespace blink
  66
  67 #endif // WebPrerenderingSupport_h