在速度模板中将String转换为Float

我怎么能将字符串转换为浮点数....由于float.parseFloat()在Apache速度下不起作用....

how wud i be able to convert string into float.... as float.parseFloat() is not working in apache velocity....

#set($sum = 0.0)
  #set($Float = 0.0)
  #set($intString = "2.2")

  #if($!intString)
     #set($sum = $sum + $Float.parseFloat($intString))
  #end

this is not working in velocity..