Insets oldMargin = this.margin; this.margin = m; firePropertyChange(MARGIN_CHANGED_PROPERTY, oldMargin, margin);
Insets oldMargin = margin; margin = m; firePropertyChange("margin", oldMargin, margin);
  public void setMargin(Insets m)  {    if (m.equals(this.margin))      {	Insets oldMargin = this.margin;	this.margin = m;	firePropertyChange(MARGIN_CHANGED_PROPERTY, oldMargin, margin);      }    this.margin = m;  }