What would be the best practice in drawing a horizontal line on an existing chart? Would love to avoid having to create a multi-axis chart as I need to do this for a ton of graphs. Basically I just want to have a few thresholds defined that show if my data is anywhere near hitting that threshold.
So for example CPU usage I want to have a line that exists at 90 (or 90%) which would indicate to the reviewer that perhaps cpu should be upgraded on this particular server if the values were near or above that threshold..
If you're using JFreeCharts, you can write a chart customizer. The JFreeChart setting is described in a couple of places:
Chart customizers require you to write a little Java and then apply it to your report.
Here's an example of a simple customizer & how to add it:
and some more info on customizers: