RequestServlet.jsp
<%
//request对象传递数据
request.setAttribute("request", "一次请求有效果");
//请求转发
request.getRequestDispatcher("page01.jsp").forward(request, response);
%>
Page01.jsp
<% pageContext.setAttribute("pageContext", "pageContext只能在当前有效,离开了当前页面就没有效果了");%>
pageContext作用范围:<%=pageContext.getAttribute("pageContext") %><br>
request作用范围:<%=request.getAttribute("request") %><br>