[Jsynthlib-devel] Bug: JSLDesktop.java

[Ton H. <a.j...@ch...>]

Hi,

I discovered a bug in JSLDesktop.getDefaultLocation.
Maybe this bug has been reported in the past.

I was trying out the Korg X3 single editor in MDI mode, and the 
following error occurred:

ERR> 'Error in PatchEditor.' reported.
ERR> [Exception] / by zero
java.lang.ArithmeticException: / by zero
         at core.JSLDesktop.getDefaultLocation(Unknown Source)
         at core.JSLFrame.moveToDefaultLocation(Unknown Source)
         at core.Actions$EditAction$Worker.run(Unknown Source)

I put some println's in the following code:

Dimension screenSize = getSize();
System.out.println(screenSize.getWidth() + " " + frameSize.getWidth() + 
" " + xofs);

int x = xofs + (xsep * frame_count) % (int) (screenSize.getWidth() - 
frameSize.getWidth() - xofs);
if (x < 0)
    x = 0;

System.out.println(screenSize.getHeight() + " " + frameSize.getHeight() 
+ " " + yofs);

int y = yofs + (ysep * frame_count) % (int) (screenSize.getHeight() - 
frameSize.getHeight() - yofs);
if (y < 0)
    y = yofs + ysep;

This was the result:

setVisible : Korg X3 Single Editor
JSynthLib finalizing...
816.0 567.0 0
488.0 488.0 0

The screen height and frame height are the same and yofs=0, so a 
division by zero occurs.
Whenever you code a division you have to check if the denominator is zero.

Regards,
Ton Holsink