gecko/content/base/public/nsDOMEventTargetWrapperCache.h

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 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
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 * The Original Code is mozilla.org code.
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 * The Initial Developer of the Original Code is
 * Wellington Fernando de Macedo.
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 * Contributor(s):
 *    Wellington Fernando de Macedo <wfernandom2004@gmail.com> (original author)
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#ifndef nsDOMEventTargetWrapperCache_h__
#define nsDOMEventTargetWrapperCache_h__

#include "nsDOMEventTargetHelper.h"
#include "nsWrapperCache.h"
#include "nsIScriptContext.h"


// Base class intended to be used for objets like XMLHttpRequest,
// EventSource and WebSocket.

class nsDOMEventTargetWrapperCache : public nsDOMEventTargetHelper,
                                     public nsWrapperCache
{
public:  
  NS_DECL_ISUPPORTS_INHERITED

  class NS_CYCLE_COLLECTION_INNERCLASS
    : public NS_CYCLE_COLLECTION_CLASSNAME(nsDOMEventTargetHelper)
  {
    NS_IMETHOD RootAndUnlinkJSObjects(void *p);
    NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED_BODY_NO_UNLINK(nsDOMEventTargetWrapperCache,
                                                            nsDOMEventTargetHelper)
    NS_IMETHOD_(void) Trace(void *p, TraceCallback cb, void *closure);
  };
  NS_CYCLE_COLLECTION_PARTICIPANT_INSTANCE
  
  void GetParentObject(nsIScriptGlobalObject **aParentObject)
  {
    if (mOwner) {
      CallQueryInterface(mOwner, aParentObject);
    }
    else {
      *aParentObject = nsnull;
    }
  }

  static nsDOMEventTargetWrapperCache* FromSupports(nsISupports* aSupports)
  {
    nsPIDOMEventTarget* target =
      static_cast<nsPIDOMEventTarget*>(aSupports);
#ifdef DEBUG
    {
      nsCOMPtr<nsPIDOMEventTarget> target_qi =
        do_QueryInterface(aSupports);

      // If this assertion fires the QI implementation for the object in
      // question doesn't use the nsPIDOMEventTarget pointer as the
      // nsISupports pointer. That must be fixed, or we'll crash...
      NS_ASSERTION(target_qi == target, "Uh, fix QI!");
    }
#endif

    return static_cast<nsDOMEventTargetWrapperCache*>(target);
  }

protected:
  nsDOMEventTargetWrapperCache() : nsDOMEventTargetHelper(), nsWrapperCache() {}
  virtual ~nsDOMEventTargetWrapperCache();
};

#endif  // nsDOMEventTargetWrapperCache_h__