private void formMouseReleased(java.awt.event.MouseEvent evt)//GEN-FIRST:event_formMouseReleased
    {//GEN-HEADEREND:event_formMouseReleased
        if (evt.getButton() == MouseEvent.BUTTON1)
        {
            if (dc_selected != null && dc_selected instanceof DCConector)
            {
                ((DCConector) dc_selected).setEnd(evt.getPoint());
            }
        }
        repaint();
    }//GEN-LAST:event_formMouseReleased