Re: [Yap-users] Java - Yap Communication

[Vitor S. C. <vi...@bi...>]

Hi Oliver,

> I'm trying to connect a Java Program to my Yap Code (Version 4.3.20).
> I start the Java through Yap with the "exec(Command,IO-List,Status)"
> Command.
> 

I have been using that command myself and it seems to be working.

> I have Problems to build up a communication between those Parts, and tried
> to do it 
> using the IO-List Parameters in exec/3 . I failed so far.
> 
> Yap-Side:
> 
> :- exec('java Frame',[user_input,user_output,user_error],Status).
> 
> :- write(MSG_O).
> 
> :- read(MSG_I).
> 
> Java-Side:
> 
> BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
> String tempString = "";
> 
> while (tempString.compareTo("eof")!= 0)  {
>        	tempString = in.readLine();
>         log.println(tempString);   // writes received MSG into a Log-File
>         System.out.println("pos.");
> }
> 

I don't understand very well what you are trying to do. You seem to be
wanting to share the standard descriptors, and I don't know if you can
use them to communicate. 

In my program what I do to communicate with a matlab process is:

	exec('matlab -nojvm -nosplash',[pipe(CommandStream),pipe(Answer),pipe(Answer)],_),

I send commands to the matlab shell using this procedure:

send_command(OStream, IStream, String, Args) :-
	format(OStream, String, Args),
	wait_for_matlab_prompt(IStream).

wait_for_matlab_prompt/1 just scans matlab until finding a matlab
prompt, which will be of the form >> or EDU>:

wait_for_matlab_prompt(Answer) :-
	fetch_prompt(Answer, -1). 

fetch_prompt(Answer, C0) :-
	get0(Answer, C1),
	( ((C0 = 0'> ; C0 = 0'U ) ,C1 = 0'> ) ->
	    true
	;
	    fetch_prompt(Answer, C1)
	).

It works fine for me (well, matlab is very slow ;-).

> Any Help or new Suggestions are Welcome.
> Thanks in advance for your Time and Help.
> 

Does this help?

Cheers,

Vitor