RE: Kawa servlet leaks

["Dominique Boucher" <dboucher at nuecho dot com>]

Hi,

Here is an update. I wrote a very dumb servlet in Java that calls a
Scheme function. The latter writes a profile in XML to the response
output stream. I wrote two versions of the Scheme function. One that
creates an output port and uses format, the other directly writes to the
output stream. In the former case, there is a leak. In the latter, no
leak. 

Dominique 

Here are the three files:

------------------------- getprofile.java
import java.io.OutputStream;
import javax.servlet.http.*;

public class getprofile extends HttpServlet
{
    public void doGet(HttpServletRequest request, 
                      HttpServletResponse response) 
    {
        OutputStream os = response.getOutputStream();
	  formatprofile.formatProfile(os);
    }
}

------------------------- formatprofile-with-leak.scm
(module-name <formatprofile>)
(module-static #t)

(define (format-profile (os :: <java.io.OutputStream>)) :: <void>
  (let ((port (make <gnu.mapping.OutPort> os)))
    (format port "<?xml version=\"1.0\" encoding=\"UTF-8\"?>~%")
    (format port "<profile>~%")
    (format port "  <id>12345</id>~%")
    (format port "  <langue>fr</langue>~%")
    (format port "  <nom>Dominique</nom>~%")
    (format port "  <sexe>M</sexe>~%")
    (format port "</profile>~%")
    (invoke os 'flush)
    (invoke os 'close)))


------------------------- formatprofile.scm
(module-name <formatprofile>)
(module-static #t)

(define (format-profile (os :: <java.io.OutputStream>)) :: <void>
  (invoke os 'write (invoke (as <String> "<?xml version=\"1.0\"
encoding=\"UTF-8\"?>\n") 'getBytes))
  (invoke os 'write (invoke (as <String> "<profile>\n") 'getBytes))
  (invoke os 'write (invoke (as <String> "  <id>12345</id>\n")
'getBytes))
  (invoke os 'write (invoke (as <String> "  <langue>fr</langue>\n")
'getBytes))
  (invoke os 'write (invoke (as <String> "  <nom>Dominique</nom>\n")
'getBytes))
  (invoke os 'write (invoke (as <String> "  <sexe>M</sexe>\n")
'getBytes))
  (invoke os 'write (invoke (as <String> "</profile>\n") 'getBytes))
  (invoke os 'flush)
  (invoke os 'close))