Custom Stock Charting

I need to rewrite my windows based application which overlays annotations on top of stock charts in java. Here are some of the high level requirements: -- the java app will run on the web server -- the java app will take a raw data feed of stock data and render the chart, I will specify the dimensions and look of the chart -- the java app will allow trend lines to be drawn on top of the chart -- the java app will be able to save the trend lines info (can be to a dat file for now) and be able to reload them on the same relative spot (this is tricky because the chart data changes slightly as more trading days go by)