<AWT Dev> OS X fullscreen window and dock

[Michael Hall]

Stack overflow or someplace like that might be better for this sort of thing, feel free to point that out if so. 
But what is the best way to get a fullscreen window, less screen offsets with a hidden dock?  While still accounting for the possible dock. I generally like to have my dock hidden but pop up when needed. That space at the bottom of the screen is valuable real estate. However, this can occasionally be a nuisance if I want to actually get to something with the mouse at the very bottom of the screen and it keeps popping up the dock in the way. 
I am currently increasing the size of the main window of one of my application’s. Going for as big as I can get it sort of full screen, hopefully less insets for the dock. I can’t seem to get this. 
For example using this…

Insets insets = this.getToolkit().getScreenInsets(this.getGraphicsConfiguration());

If I have the dock not visible but appearing automatically I get…
1/8/17 8:25:15.350 AM JavaAppLauncher[3384]: Insets java.awt.Insets[top=23,left=0,bottom=4,right=0]
No dock is accounted for at the bottom.

If I change this to always visible I get...
1/8/17 8:51:57.881 AM JavaAppLauncher[3430]: Insets java.awt.Insets[top=23,left=0,bottom=43,right=0]
There is the dock. 

How can I determine the correct value as below when the user preferences are set to not always visible as in the above?

Michael Hall