png « JFreeChart « JSP-Servlet Q&A

2. can I have non-image (gif,png) jfreechart in servlet?

The Developer's guide showed a simple servlet with JFreeChart by converting the chart to a png. Is there any way I can show the jfreechart as is in a servlet? I want to keep the chart's features (zooming and etc). If it is possible, what is the common mime type? Would it be application/octet-stream ? Thanks.