Installed the new Raspbian OS (Debian Stretch) on my Pi2 and PI3 today using the normal repositories by:
sudo apt-get install geogebra
When I went to run it, the program did not appear to start. Ran it from the terminal (cli) and geogebra returned with its first error looking something like the following:
I fixed this by editing the file /etc/java-8-openjdk/accessibility.properties (use your favorite editor, Raspbian comes with leafpad too. I used nano as my text editor. Switch nano with leafpad to get a full graphical text editor in the below line if you prefer to use leafpad. It is a little easier to use.)
sudo nano /etc/java-8-openjdk/accessibility.properties
Comment out the following line as shown below (you are adding # as the first character of the line to do this):
Actually this was the only uncommented line in the file.
Geogebra started up fine after that. This has apparently caused similar problems with other programs since I found this fix on the Internet when I searched for java.awt.Toolkit.loadAssistiveTechnologies. If someone else experiences this problem I hope my note helps them.