[webkit-dev] JavaJSObject vs JSObject

[Per Bothner]

On 03/21/2011 03:17 PM, Darin Adler wrote:
> JavaScript bindings living outside WebKit that are written today should use the stable JavaScriptCore API, the functions in header files such as JSClassRef.h. Doing it that way you can make something that will continue to work for a long time. If you use the internals the code may constantly need revision.

Thanks.  It appears the 2 types I need to primarily deal with are
JSObjectRef and JSContextRef.

JSObjectRef seems straight-forward: It's a struct OpaqueJSValue*,
which is the same a JSC::JSObject*, and I get the latter from the
former using toRef from APICast.h.

JSContextRef is a little trickier: It seems equivalent to an ExecState*.
Presumably we'd want a JSGlobalContextRef, so using toGlobalRef
make sense.  Our codebase has code like:
   JSGlobalContextRef globalContext =
 
toGlobalRef(frame()->script()->globalObject(mainThreadNormalWorld())->globalExec());
That works, but it would be nice if there were a cleaner way to do it ...

Some Googling found references to webkit_web_frame_get_global_context() and
WebFrame::globalContext() but I didn't find these - maybe they're 
Cacoa-specific?

Is it better to search for JSGlobalContextRef on each method call, or should
it be stashed in a field of the Java JSObject wrapper?  The latter might be
more efficient, but only as long as a the JSGlobalContextRef is stable.
-- 
	--Per Bothner
per.bothner at oracle.com   per at bothner.com   http://per.bothner.com/