<s:generator separator="," val="'书法,音乐,运动'" id="mylove" count="2" />
      <%
           Iterator it = (Iterator)pageContext.getAttribute("mylove") ;
           int i = 1 ;
           while(it.hasNext()){
              out.print((i++)+","+it.next()+"<br/>") ;
           }
       %>
报如下错误：
严重: Servlet.service() for servlet jsp threw exception
java.lang.NullPointerException
那位大侠帮忙看看！！谢谢了！