SessionServlet.jsp
<!doctype html public "-//w3c/dtd HTML 4.0//en">
<html>
<!-- Copyright (c) 1999-2000 by BEA Systems, Inc. All Rights Reserved.-->
<head>
<title>Session Servlet</title>
</head>
<body bgcolor="#FFFFFF">
<font face="Helvetica">
<h2>
<font color=#DB1260>
Session Servlet
</font>
</h2>
<p>
This servlet demonstrates the use of HTTP sessions. You can add or delete
named values to a session. The same session can be retrieved next time the
user visits the page via a browser cookie. Use this form to see your additions
and deletions at work. Check the code to see how adding and deleting session
name/value pairs works.
</p>
<%
if (request.getParameter("AddValue") != null) {
session.setAttribute(addPrefix(request.getParameter("NameField")),
request.getParameter("ValueField"));
} else if (request.getParameter("DeleteValue") != null) {
session.removeAttribute(addPrefix(request.getParameter("NameField")));
}
%>
<center>
<table border=1 cellspacing=2 cellpadding=5 width=400 bgcolor=#EEEEEE>
<th colspan=2>Session<br>
</th>
<tr>
<td><B>Name</B></td>
<td><B>Value</B></td>
</tr>
<%
Enumeration sessionNames = session.getAttributeNames();
String name;
while (sessionNames.hasMoreElements()) {
name = (String)sessionNames.nextElement();
%>
<tr>
<td><%= removePrefix(name) %></td>
<td><%= (String)session.getAttribute(name) %></td>
</tr>
<%
} // end of while loop for session names
%>
</table>
</center>
<p>
<form method="post" name="SessionServlet" action="SessionServlet.jsp">
<center>
<table border=0 cellspacing=2 cellpadding=5 width=400>
<th>Name to add/delete</th>
<th>Value</th>
<tr>
<td><input type="text" name="NameField"></td>
<td><input type="text" name="ValueField"></td>
</tr>
<tr>
<td colspan=2 align=center><input type="submit" value=" Add " name="AddValue"></td>
</tr>
<tr>
<td colspan=2 align=center><input type="submit" value="Delete" name="DeleteValue"></td>
</tr>
</table>
</center>
</form>
<p>
<font size=-1>Copyright (c) 1999-2000 by BEA Systems, Inc. All Rights Reserved.
</font>
</font>
</body>
</html>
<%!
static final String PREFIX_LABEL="SessionServlet.";
private String removePrefix(String name) {
if (name.startsWith(PREFIX_LABEL))
name = name.substring(PREFIX_LABEL.length());
return name;
}
private String addPrefix(String name) {
if (!name.startsWith(PREFIX_LABEL))
name = PREFIX_LABEL + name;
return name;
}
%>