如何在velocity template中优雅的获取当前时间

#set( $str = "" )
#set( $dt = $str.getClass().forName("java.util.Date").newInstance() )
#set( $y = $dt.year + 1900 )
#set( $m = $dt.month )
#set( $d = $dt.date )
${y}-${m}-${d}