/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import java.io.IOException;
import java.io.PrintWriter;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.Date;
import java.util.Enumeration;
import java.util.ResourceBundle;
import jakarta.servlet.ServletException;
import jakarta.servlet.http.HttpServlet;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import jakarta.servlet.http.HttpSession;
import util.HTMLFilter;
/**
* Example servlet showing request headers
*/
public class SessionExample extends HttpServlet {
private static final long serialVersionUID = 1L;
private static final int SESSION_ATTRIBUTE_COUNT_LIMIT = 10;
@Override
public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
ResourceBundle rb = ResourceBundle.getBundle("LocalStrings", request.getLocale());
response.setContentType("text/html");
response.setCharacterEncoding("UTF-8");
PrintWriter out = response.getWriter();
out.println("<!DOCTYPE html><html>");
out.println("<head>");
out.println("<meta charset=\"UTF-8\" />");
String title = rb.getString("sessions.title");
out.println("<title>" + title + "</title>");
out.println("</head>");
out.println("<body bgcolor=\"white\">");
out.println("<a href=\"../sessions.html\">");
out.println(
"<img src=\"../images/code.gif\" height=24 " + "width=24 align=right border=0 alt=\"view code\"></a>");
out.println("<a href=\"../index.html\">");
out.println(
"<img src=\"../images/return.gif\" height=24 " + "width=24 align=right border=0 alt=\"return\"></a>");
out.println("<h3>" + title + "</h3>");
HttpSession session = request.getSession(true);
out.println(rb.getString("sessions.id") + " " + session.getId());
out.println("<br>");
out.println(rb.getString("sessions.created") + " ");
out.println(new Date(session.getCreationTime()) + "<br>");
out.println(rb.getString("sessions.lastaccessed") + " ");
out.println(new Date(session.getLastAccessedTime()));
// Count the existing attributes
int sessionAttributeCount = 0;
Enumeration<String> names = session.getAttributeNames();
while (names.hasMoreElements()) {
names.nextElement();
sessionAttributeCount++;
}
String dataName = request.getParameter("dataname");
String dataValue = request.getParameter("datavalue");
if (dataName != null) {
if (dataValue == null) {
session.removeAttribute(dataName);
sessionAttributeCount--;
} else if (sessionAttributeCount < SESSION_ATTRIBUTE_COUNT_LIMIT) {
session.setAttribute(dataName, dataValue);
sessionAttributeCount++;
} else {
out.print("<p> Session attribute [");
out.print(HTMLFilter.filter(dataName));
out.print("] not added as there are already "+ SESSION_ATTRIBUTE_COUNT_LIMIT + " attributes in the ");
out.println("session. Delete an attribute before adding another.");
}
}
out.println("<p>");
out.println(rb.getString("sessions.data") + "<br>");
names = session.getAttributeNames();
while (names.hasMoreElements()) {
String name = names.nextElement();
String value = session.getAttribute(name).toString();
out.println(HTMLFilter.filter(name) + " = " + HTMLFilter.filter(value));
out.print("<a href=\"");
out.print(HTMLFilter.filter(
response.encodeURL("SessionExample?dataname=" + URLEncoder.encode(name, StandardCharsets.UTF_8))));
out.println("\" >delete</a>");
out.println("<br>");
}
if (sessionAttributeCount < SESSION_ATTRIBUTE_COUNT_LIMIT) {
out.println("<p>");
out.print("<form action=\"");
out.print(response.encodeURL("SessionExample"));
out.print("\" ");
out.println("method=POST>");
out.println(rb.getString("sessions.dataname"));
out.println("<input type=text size=20 name=dataname>");
out.println("<br>");
out.println(rb.getString("sessions.datavalue"));
out.println("<input type=text size=20 name=datavalue>");
out.println("<br>");
out.println("<input type=submit>");
out.println("</form>");
out.println("<p>GET based form:<br>");
out.print("<form action=\"");
out.print(response.encodeURL("SessionExample"));
out.print("\" ");
out.println("method=GET>");
out.println(rb.getString("sessions.dataname"));
out.println("<input type=text size=20 name=dataname>");
out.println("<br>");
out.println(rb.getString("sessions.datavalue"));
out.println("<input type=text size=20 name=datavalue>");
out.println("<br>");
out.println("<input type=submit>");
out.println("</form>");
out.print("<p><a href=\"");
out.print(HTMLFilter.filter(response.encodeURL("SessionExample?dataname=exampleName&datavalue=exampleValue")));
out.println("\" >URL encoded </a>");
} else {
out.print("<p>You may not add more than " + SESSION_ATTRIBUTE_COUNT_LIMIT + " attributes to this session.");
}
out.println("</body>");
out.println("</html>");
}
@Override
public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
doGet(request, response);
}
}