A working XPCom component made in Java

Now I have a ready and working solution. An XPCom component implemented in Java, which externally uses a bit of JavaScript.
 
As described on my last message, I tried to instantiate the java classes by javaConnect´s ComponentManager.
Later, I discovered the problem was that XPIDL interface could not match exactly the java interfaces, so there should be a translation.
The differences are that java methods start with lower letters and the properties are accessed by get/set methods.
 
In my solution, I created one JavaScript module to wrap each Java class and relate each java method to the expected interface attribute/method, making the Java-to-XPIDL translation.
Maybe this translation could be done generically, by changing the JavaClassLoader package from Java Firefox Extension.
 
Any further suggestions?
 
----------------
Murilo Perrone
CertiSign
 
-----Mensagem original-----
De: [email protected] [mailto:[email protected]]Em nome de Murilo Camões Perrone
Enviada em: terça-feira, 10 de janeiro de 2006 15:44
Para: Mozilla-Java
Assunto: RES: JavaConnect and JavaScript
 
Javier Pedemonte,
 
Your example (below) is nice way of using the Java code from mozilla.
 
nsIServiceManager sm = Mozilla.getServiceManager();
nsIWindowWatcher watcher = (nsIWindowWatcher) sm
.getServiceByContractID(NS_WINDOWWATCHER_CONTRACTID,
nsIWindowWatcher.NS_IWINDOWWATCHER_IID);
watcher.setWindowCreate(WindowCreator);

Though, I need to entirelly use the XPIDL interface of my XPCom component from withing JavaScript code. 
Currently I am being able to instantiate Java objects from JavaScript as XPCom objects implementing XPIDL interfaces.
 
JavaScript test code:
 
    var certs = Components.classes[javaXPComComponentID].getService(Components.interfaces.ICertificates);
 
    alert( "certs = " + certs ); // certs = [xpconnect wrapped (nsISupports, ICertificates)]
    alert( "certs.Count = " + certs.Count ); // certs.Count = 0
    alert( "certs.Clear = " + certs.Clear ); // certs.Clear = function Clear() { [native code] }
    certs.Clear(); // exception is thrown with code NS_ERROR_XPC_JSOBJECT_HAS_NO_FUNCTION_NAMED
 
So I could sucessfully access the attributes defined on XPIDL interface with no get/set prefix, but there is a problem when calling the methods (which are also described on the XPIDL interface).
 
I followed the steps in Java Firefox Extension example, except that I added a shortcut so that the java object will be returned directly from Mozilla´s Component Manager, and thus used by JavaScript as defined on the XPIDL interface (such as ICertificates.xpt).
 
In my JavaScript component, the factory´s createInstance method returns new Java object instances. First, it loads the class from a “package.classname” string, then instantiates it calling the constructor.
 
To avoid the NS_ERROR_XPC_JSOBJECT_HAS_NO_FUNCTION_NAMED error, I will try to add an extra step in the process of loading the Java class.
I will use the JavaConnect´s XPCOM class instead of just calling the class constructor.
 
nsIComponentManager componentManager = XPCOM.getComponentManager();
componentManager.createInstanceByContractID( ICERTIFICATES_CONTRACTID, null, ICERTIFICATES_IID);
 
Then XPConnect AND JavaConnect would be both used together.
 
The two instructions above could be used in different ways:
*        from within Java code, returning an nsISupports object
*        from within JavaScript, loading XPCOM class
*        maybe even from C++ code (if that would be usefull), using JavaConnect´s DLL function entries
 
Makes sence?
 
Also, from were can I download updated JavaConnect sources?
 
The XulRunner nighty zip from the link below does not include it.
 
http://ftp.mozilla.org/pub/mozilla.org/xulrunner/nightly/latest-mozilla1.8/
 
----------------
Murilo Perrone
CertiSign