www.jfree.org

While not strictly a stock ticker application, I need the following functionality

1. a bar type graph of count vs date - I'm thinking YES
2. moderately large data set (say 10 - 50 years worth of days) so I'd like to display only a subset and be able to scroll left and right via a slider control . I'm wondering if dynamically loading and unloading the data outside the "window" is possible, or needed.
3.change views , for example, dynamically from counts per day to counts per year

Thanks

Take a look at the demo in this post
http://www.jfree.org/phpBB2/viewtopic.php?t=24606

It demo's points 1 & 2.

For #3 you would just need to create 2 datasets that represent the count/day, count/year and call plot.setDataset() to change the data.