JACE, the Java Apple Computer Emulator has been updated.  Per Brendan Robert’s comp.sys.apple2 post:

1) Concurrent modification exceptions have been eradicated when you apply settings changes.  These used to kill the emulation when you used the config screen to tweak settings or change disks.  I am very happy to say it works correctly as it was intended to work from the get go.  You can even switch to the ][DB debugger rom in mid-session without a crash!  Also supported are changing out card assignments, though some software only detects on start so you might have to use a three-fingered salute anyway.

2) Frame generation is now cycle-perfect, so split screen modes work as expected

3) Other video generation controls are provided, so it is possible to slow down the scanner, or change where HBL is generated from.  This seems rather silly, but for some reason it is the only way to get certain things (floating bus rainbow example) to work for now (default settings are compatible)

4) It is also possible to beautifully render the money munchers title, just set the HBL x/y offsets to 0 and set the scan interval to 3.  I’m not sure why, but this is the only way I could get it to stop flickering madly, though I know it is not **correct** at all.

Download the latest build here.