if(value != this.value) {
if ((value == null && this.value != null) || (value != null && ! value.equals(this.value))) {
  public void setValue(Object value) {    if(value != this.value) {      Object old = this.value;      this.value = value;      try {	fireValueChanged(old);      } catch (RuntimeException re) {	this.value = old;	throw re;      }    }  }