extensions/renderer/native_handler.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 EXTENSIONS_RENDERER_NATIVE_HANDLER_H_
   6 #define EXTENSIONS_RENDERER_NATIVE_HANDLER_H_
   7
   8 #include "base/basictypes.h"
   9 #include "v8/include/v8.h"
  10
  11 namespace extensions {
  12
  13 // NativeHandlers are intended to be used with a ModuleSystem. The ModuleSystem
  14 // will assume ownership of the NativeHandler, and as a ModuleSystem is tied to
  15 // a single v8::Context, this implies that NativeHandlers will also be tied to
  16 // a single v8::Context.
  17 // TODO(koz): Rename this to NativeJavaScriptModule.
  18 class NativeHandler {
  19  public:
  20   NativeHandler();
  21   virtual ~NativeHandler();
  22
  23   // Create a new instance of the object this handler specifies.
  24   virtual v8::Local<v8::Object> NewInstance() = 0;
  25
  26   // Invalidate this object so it cannot be used any more. This is needed
  27   // because it's possible for this to outlive its owner context. Invalidate
  28   // must be called before this happens.
  29   //
  30   // Subclasses should override to invalidate their own V8 state. If they do
  31   // they must call their superclass' Invalidate().
  32   //
  33   // Invalidate() will be called on destruction, if it hasn't already been.
  34   // Subclasses don't need to do it themselves.
  35   virtual void Invalidate();
  36
  37  protected:
  38   // Allow subclasses to query valid state.
  39   bool is_valid() { return is_valid_; }
  40
  41  private:
  42   bool is_valid_;
  43
  44   DISALLOW_COPY_AND_ASSIGN(NativeHandler);
  45 };
  46
  47 }  // namespace extensions
  48
  49 #endif  // EXTENSIONS_RENDERER_NATIVE_HANDLER_H_