指令元素:page、include、taglib
---include指令:<%@ include file="URL"%>
---include动作:<jsp:include page="URL" flush="true|false">
---include指令与include动作区别
---forward动作:<jsp:forward page="URL">
等同于服务器跳转指令:request.getRequestDispatcher("/url").forward(request,response);
---param动作:<jsp:param name="参数名" value="参数值">
常常与<jsp:forward>一起使用,作为其的子标签。