To keep an image in the Server

[jesusmgmarin]

I am using Debian + tomcat + j2sdk1.4.2_10 + jfreechar-1.0.1 ...

I have a doubt on how adding a functionality. I have a page in jsp that loads an Applet, this Applet loads a Servlet which generates a graph with JFreeChart. This works correctly, but in the Servlet I have:

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........
  response.setContentType("image/jpeg");
  
  OutputStream myOutStream = response.getOutputStream();
  JFreeChart myChart  = crearChart();
        
  int ancho = getParamEntero(request,"ancho",400);
  int alto = getParamEntero(request,"alto",300);
        
  ChartUtilities.writeChartAsJPEG(myOutStream,myChart,ancho,alto);
  ChartUtilities.saveChartAsJPEG(new File("/usr/local/tomcat/webapps/Usuarios/graph1.jpg"), myChart, ancho, alto);
 
  myOutStream.close();
.....

Servlet separately works correctly (it keeps the image in the Server, in the indicated directory). And the Applet also works correctamente( It loads the Servlet and shows the Servlet), but what it does not work to me it is:

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ChartUtilities.saveChartAsJPEG(new File("/usr/local/tomcat/webapps/Usuarios/graph1.jpg"), myChart, ancho, alto);

The image in the Server does not keep (when I do this with the Applet).


Somebody can say to me why does not keep the image?
Thanks.[/b]

[angel]

I have a page in jsp that loads an Applet, this Applet loads a Servlet which generates a graph with JFreeChart.

Sorry, but this seems to be very odd. Why do you need the Applet, when you have a server in the backend which generates the chart for you???

[jesusmgmarin]

Hi, and thanks for write me.

I have been able to load and that the Servlet works that generates the graph, but ademas of the graph I want to show more texts in servlet.
In servlet I have (so that it shows gráfica)

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    response.setContentType("image/jpeg");

and I have tried to put

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    response.setContentType("text/html");
    PrintWriter out = response.getWriter();

soon so that it can write using out.println("..."); but I have not obtained the form to do it.
Therefore treatment of which the applet loaded servlet in the page jsp, and this way I can add more text.

If there is form to do first that I have put, How?

Thanks!![/code]

[angel]

Have you tried to generate an HTML page with the servlet? There you can put an <img> tag with the url of the chart and also include additional text.

[jesusmgmarin]

Thanks very much.

I didn´t know that a Servlet that generates a graph could be invoked with the tag <img>

Now it runs