ruby未初始化常量

我经常会遇到这样的错误:

未初始化的常量GetxmlController::Xmlparse

require "rexml/document"
include REXML

Class Xmlparse
  def parsetime
    xmlfile = File.new("colors.xml")
    xmldoc = Document.new(xmlfile)
    root = xmldoc.root
    return root
  end
end

我的控制器看起来像:

class GetxmlController < ApplicationController
  def findxml
    @hxml=Xmlparse.new
    @test1=@hxml.parsetime
  end
end