//implicit.jsp
<%@ page language= "java" %>
<html>
<head><title>Implicit</title></head>
<body>
<p>
<%=
session.getAttribute("s1")+request.getParameter("t1")+session.getAttribute("s2")
%>
</p>
</body>
</html>
//implicit,.html
<%@ page language= "java" %>
<html>
<%!
String str1 = new String(" ");
String str2 = new String(" ");
%>
<%
HttpSession ses = request.getSession(true);
str = request.getParameter("t1");
ses.setValue("s1",str1);
ses.setValue("s2",str2);
%>
<body>
<form method=post action="implicit.jsp">
<input type = text name="t1" >
<input type=submit>
</form>
</body>
</html>