[mapserver-users] Java MapScript and Tomcat6 Hanging

[Gilbertson, Paul]

Good folks,

I am somewhat new to MapServer and MapScript, and I'm trying to do a few experiments with Java Mapscript in order to scope out MapServer's feasibility for a large project.

I've downloaded and installed MS4W 3.0 beta 11, and Netbeans 6.9 with Tomcat 6.0.29 in order to test out Java Mapscript. I created a most basic servlet to serve up simple map tiles, and it works for serial requests. When I try to serve two requests at the same time Tomcat hangs hard.

My map file and Java classes are below:

MAP
  IMAGETYPE      PNG24
  NAME           "nbndemo"
  STATUS         ON
  EXTENT         -12.5 12.5 700000 1300012.5
  SIZE           800 800
  IMAGECOLOR     226 245 255
  CONFIG         "MS_ERRORFILE" "/ms4w/apps/nbndemo/error.txt"
  DEBUG          5

  PROJECTION
    "init=epsg:27700"
  END
 
  LAYER 
    NAME         os250k
    STATUS       ON
    TILEINDEX    "/OSRasterTiles/os_250k/os250k_tindex_srs.shp"
    TILEITEM     "Location"
    TYPE         RASTER
    OFFSITE      71 74 65

    PROJECTION
      "init=epsg:27700"
    END
    EXTENT         -12.5 12.5 700000 1300012.5
  END 
END

public class SPRewriter {
    public synchronized void doLogic(HttpServletRequest request, HttpServletResponse response) throws Exception   
    {
        ServletOutputStream out = response.getOutputStream();
        edu.umn.gis.mapscript.mapObj mo = new mapObj("/ms4w/apps/nbndemo/mapfiles/test.map");

        imageObj image = mo.draw();
        response.setContentType(image.getFormat().getMimetype());
        out.write(image.getBytes());
        image.delete();
        mo.delete();
    }
}

    protected void processRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        try {
            SPRewriter spr = new SPRewriter();
            spr.doLogic(request, response);
        }  catch (Exception e) {
            e.printStackTrace();
        }
    }

Any thoughts why this would hang the moment I try to run parallel requests?

Regards,
Paul Gilbertson



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