Exception in thread "Timer-0" org.eclipse.swt.SWTException: Invalid thread access

This exception is thrown when an SWT operation is performed from a non-UI thread. SWT is a user interface toolkit used in Java applications, and it requires all UI-related operations to be performed from the UI thread.

To fix this exception, you need to ensure that any SWT-related operations are performed from the UI thread. This can be achieved by using the `Display.asyncExec()` or `Display.syncExec()` methods, which execute a Runnable on the UI thread.

For example, if you have a Timer that updates a SWT component, you can wrap the update code in a `Display.asyncExec()` block:

Timer timer = new Timer();
timer.schedule(new TimerTask() {
    @Override
    public void run() {
        Display.getDefault().asyncExec(new Runnable() {
            public void run() {
                // Update SWT component here
            }
        });
    }
}, 0, 1000);

This ensures that the update code is executed on the UI thread and avoids the Invalid thread access exception.