🚀 go-pugleaf

BH wrote:

> We're new to java and wondering about the prospects of easing it into 
> our current non-java apps until they are eventually 100% java....
>
> Is it possible to "blend" java desktop or C/S app widgets (not 
> web/browser stuff) with a win32 app such that the java portions appear 
> to be part of the calling win32 app or dll?  

Not without some difficulty, but it's not impossible.

The problem is that the Java stuff needs a JRE to run, so for starters, 
you'll have to bundle a JRE.

The normal code sequence to load and run Java code from C/C++ code is to 
use "JNI" (the Java Native Interface) to create a virtual machine, and 
feed it code to execute.

However, in your case, where you have a C/C++ DLL that you want to ship, 
and have various entry points in it (which can be called in any sequence 
or selection) turn around and call Java code, you probably want to 
create some sort of "helper class" that'll load the VM once (on first 
invocation), and then invoke the Java code underneath.

In order to make this easier to encapsulate, your Java code should 
probably implement some standard interface, so that the boilerplate code 
to invoke it and pass parameters can be shared by the various library 
entry points..

So the short answer is again: yes, it can be done, but it might be 
painful and messy.
--
Shankar.