JScrollPane sp = new JScrollPane();
sp.getHorizontalScrollBar().addAdjustmentListener( new AdjustmentListener() {
  public void adjustmentValueChanged(AdjustmentEvent ae) {
    dbg("adjust: " + ae);
    dbg("source: " + ae.getSource());
    if ( ae.getSource() instanceof JScrollBar) {
        ((JScrollBar) ae.getSource()).setValue(0);
    }
  }
});

//
//
Declare:
	public AdjustmentListener al = new AdjustmentListener() {
		public void adjustmentValueChanged(AdjustmentEvent ae) {
			System.out.println("doReset=" + doReset +", " + ae.paramString() );
			if (doReset) {
				System.out.println("RESET =" + ae);
				doReset = false;
			 	((JScrollBar) ae.getSource()).setValue(0);
				doReset = false;
			}
			//}
		}
	};
	private static boolean doReset = true;

void init() {
JScrollPane sp = new JScrollPane();
sp.getHorizontalScrollBar().addAdjustmentListener(al);
setScrollList(sp);
}

/* Some Event like TreeExpansion, TreeCollapse etc.. With invoke this method */
void align() {
   doReset = true;
}