How to make a JSR-168 portlet with a chart?

Question

I'm trying to make a JSR-168 portlet with a chart. Studying about it i can run some portlets in NetBeans with portlet-container but i have to make some charts to run too. Can some one help with a LINK or an Example? I found that to help me:

-> dojocampus.org -> dojotoolkit.org -> extjs.com

I make a chart, but when i put on portlet-container have the error: "Deployment Failed Portlet war file. Possible reason can be error reading WEB-INF/portlet.xml from portlet war file". Only the portlet or the chart they work, but toghetter make the error. JSR can run any chart type(flash, Java Script, etc)?

Att

Answer 1

The easiest(even not perfect) way is to create a ordinary servlet which receives the values as input parameters and output would be the picture.

Here is some basic info how to create dynamic image in servlet: http://www.exampledepot.com/egs/javax.servlet/GetImage.html

To generate image of graph you can use this library: http://www.jfree.org/jfreechart/index.html