This Java Applet Tutorial seems more current than most of the Applet tutorials I've found. It explains the difference between Applet and JApplet and other useful things.
Some of the code has copyright date of 2008 (of course, that might just be an automatically updated date.) The tutorial recommends using the APPLET tag which has been deprecated.
I compiled several of the samples. They did not crash my browser.
I probably would have been happy if I found this tutorial before all the old ones with broken code.
I think I will give up on interactive graphics for the moment.
In this last week, I've read one too many essays on why Java programmers are superior to all other forms of life on the planet (Java programmers use superior thinking which makes them superior beings). Quite frankly, I have no need for superior beings with superior forms of thought.