components/translate/content/browser/browser_cld_data_provider_factory.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 COMPONENTS_TRANSLATE_CONTENT_BROWSER_BROWSER_CLD_DATA_PROVIDER_FACTORY_H_
   6 #define COMPONENTS_TRANSLATE_CONTENT_BROWSER_BROWSER_CLD_DATA_PROVIDER_FACTORY_H_
   7
   8 #include "base/macros.h"
   9 #include "base/memory/scoped_ptr.h"
  10 #include "components/translate/content/browser/browser_cld_data_provider.h"
  11
  12 namespace content {
  13 class WebContents;
  14 }
  15
  16 namespace translate {
  17
  18 // A factory for the Browser side of CLD Data Providers. The embedder should
  19 // set an instance as soon as feasible during startup. The browser process will
  20 // use this factory to create the one BrowserCldDataProvider for each render
  21 // view host in order to communicate with a RendererCldDataProvider in the
  22 // renderer process. For more information on the RendererCldDataProvider, see:
  23 //   ../renderer/renderer_cld_data_provider.h
  24 class BrowserCldDataProviderFactory {
  25  public:
  26   BrowserCldDataProviderFactory() {}
  27   virtual ~BrowserCldDataProviderFactory() {}
  28
  29   // Create and return a new instance of a BrowserCldDataProvider. The default
  30   // implementation of this method produces a no-op BrowserCldDataProvider that
  31   // is suitable only when CLD data has been statically linked.
  32   // Every invocation creates a new provider; the caller is responsible for
  33   // deleting the object when it is no longer needed.
  34   virtual scoped_ptr<BrowserCldDataProvider> CreateBrowserCldDataProvider(
  35       content::WebContents* web_contents);
  36
  37   // Returns true if and only if the current instance for this process is not
  38   // NULL.
  39   static bool IsInitialized();
  40
  41   // Sets the default factory for this process, i.e. the factory to be used
  42   // unless the embedder calls Set(BrowserCldDataProviderFactory*). This is the
  43   // method that normal (i.e., non-test) Chromium code should use; embedders can
  44   // and should use the unconditional Set(BrowserCldDataProviderFactory*) method
  45   // instead. If a default factory has already been set, this method does
  46   // nothing.
  47   static void SetDefault(BrowserCldDataProviderFactory* instance);
  48
  49   // Unconditionally sets the factory for this process, overwriting any
  50   // previously-configured default. Normal Chromium code should never use this
  51   // method; it is provided for embedders to inject a factory from outside of
  52   // the Chromium code base. Test code can also use this method to force the
  53   // runtime to have a desired behavior.
  54   static void Set(BrowserCldDataProviderFactory* instance);
  55
  56   // Returns the instance of the factory previously set by Set()/SetDefault().
  57   // If no instance has been set, a default factory will be returned that
  58   // produces no-op BrowserCldDataProviders as described by
  59   // CreateBrowserCldDataProvider(...) above.
  60   static BrowserCldDataProviderFactory* Get();
  61
  62  private:
  63   DISALLOW_COPY_AND_ASSIGN(BrowserCldDataProviderFactory);
  64 };
  65
  66 }  // namespace translate
  67
  68 #endif  // COMPONENTS_TRANSLATE_CONTENT_BROWSER_BROWSER_CLD_DATA_PROVIDER_FACTORY_H_