Quick 5.1 JSP clustering question...

Does JSP/servlet clustering (WL 5.1) absolutely require a proxy sitting in
          front of the clustered servers?
          Brian Dainton
          Pervado Systems, Inc.
          www.pervado.com

Yes.
          Brian Dainton wrote:
          > Does JSP/servlet clustering (WL 5.1) absolutely require a proxy sitting in
          > front of the clustered servers?
          >
          > Brian Dainton
          > Pervado Systems, Inc.
          > www.pervado.com

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Hi SDN Guru's,
I have seen quick poll functionality for one question followed by answers,
but i have a reauirement to have instant survey of 5 or 10 questions and get the poll is this possible with the current quickpoll if not how can we do that.
please provide suggestions , alternatives workarounds
Thanks in advance,
Murali

Hi,
Quick Poll as name suggests is for simple and faster polls. So by default, it is meant to have one question only.
1) If you want many questions, then you may have to create some JSP application for it and make it an iView.
2) There is also option for using many campaigns, each campaign for each question. That way all the questions will be visible at the same time. But I'll not suggest it if all questions are based on same topic. In that case, only custom application will be better.
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Hi. I have a quick question. I have a client jsp page with a table, listing all the fields from my mySQL table called kellybclients. At the end of each row, I also have a submit button that I would like navigate the user to the campus jsp page that only shows the data associated with the client who's button they clicked on in the table. I'm trying to figure out how to pass this data from my JSP into the rowset.setCommand method in my connection/data bean. I am using a cached row set. Here's the code from my bean:
* To change this template, choose Tools | Templates
* and open the template in the editor.
package ETS;
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So the button should be a Submit button for a form. There are a couple of different methods for doing this:
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<table><form action="selectClient" method="post">
<tr><td> etc </td><td><input type="submit" name="submit__id_1"/></td></tr>
<tr><td> etc </td><td><input type="submit" name="submit__id_2"/></td></tr>I think most people end up doing some variant of 3, which I don't like because I hate to rely on JavaScript to make my web apps work properly. I would prefer 4, which takes more work on the server side (which I like better) but 1 works just as well with a lot more typing and uglier HTML code. Actually, I would like 2 the best because that is pretty much what the <button> element was designed for, but Microsoft screwed that up.

Harm, looking for a quick answer on a RAID question...

I bought a G-Speed ES drive with the G-Tech RAID card, set up the drive yesterday, initialized it (took 9 hours!) as a RAID-5, and in the initiallization settings window I was asked what sector size I wanted. I did some quick research and found that bigger sectors are better with bigger files, so choose the maximum size available to me under the hardware RAID, which was 4k (I'm assuming that's 4096). Came into the office this morning and found the drive had finished the initilization and that Windows required me to create a "simple volume" on it before it could be used. I'm in the process of doing that, and have found that Windows is asking me to set a sector size again: This time my maximum option is 64k. Do I want to go with the maximum option of 64k, or do I have to use the 4096 which the hardware RAID used in initializing the array?

David,
This may be informative: http://www.tomshardware.com/reviews/wd-4k-sector,2554-3.html
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I have some questions about clustering in Ironport:
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We received a second Ironport for setup a cluster configuration between them.
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PS: Sorry for my english

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Edited by: user12259190 on Feb 8, 2010 7:04 AM

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I'm a webmaster for a non-profit site and I'm looking into adding some
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either u can make use of
<jsp:usebean scope="application" id="<InstanceName>" class="<CLASS_NAME>" >or make use of scriptlets code
<%
Vector<Object> oBj = (Vector<Object>) application.getAttribute("<AttributeName>");
%>

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I have a servlet that is executing a few queries against a database. I am fowarding the results to a jsp page to display the results. I have been able to do this. My problem is when my query selects more than one field I am unsure on how to read that into an array or something like that. All the results I have done so far have had multiple results but only from one field in the database. Here is my serlvet and jsp code. If some one could tell me how to read multiple field into an array and display them on a jsp page that would be great. Thank you
Servlet
package nnet;
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
import java.security.Principal;
import java.sql.*;
import java.sql.DriverManager;
* <p>Title: NNET</p>
* <p>Description: Northland Intranet</p>
* <p>Copyright: Copyright (c) 2004</p>
* <p>Company: NMI</p>
* @author not attributable
* @version 1.0
public final class home
extends HttpServlet {
//Initialize global variables
//Initialize queries
private static final String USERQUERY =
"SELECT public.tblindividual.firstname as firstname " +
"FROM public.tblloginname " +
"INNER JOIN public.tblindividual ON (public.tblloginname.indlink = public.tblindividual.indid) " +
"WHERE LOWER(public.tblloginname.loginname) = LOWER(?)";
private static final String MAINLINKQUERY =
"SELECT public.nnetsection.name " +
"FROM public.nnetsection " +
"WHERE public.nnetsection.posted = 'true'";
private static final String ANOUNCEMENTQUERY =
"SELECT public.nnetanouncement.anouncement, to_char(nnetanouncement.postdate,'MonthDD, YY') as postdate " +
"FROM public.nnetanouncement " +
"ORDER BY public.nnetanouncement.postdate DESC";
public void init() throws ServletException {
//Process the HTTP Get request
public void doGet(HttpServletRequest request, HttpServletResponse response) throws
ServletException, IOException {
Connection con = null;
PreparedStatement stmt = null;
//Initialize Resultset objects
ResultSet namers = null;
ResultSet mainlinkrs = null;
ResultSet anouncementrs = null;
ResultSet anouncementdaters = null;
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ArrayList mainlinkresults = new ArrayList();
ArrayList anouncementresults = new ArrayList();
String firstnameresult = null;
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String username = user.getName();
Properties props = new Properties();
InputStream in = getServletContext().getResourceAsStream(
"/WEB-INF/sql.properties");
props.load(in);
in.close();
//get Users login name to pass on
try {
Class.forName(props.getProperty("connection.driver"));
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stmt = con.prepareStatement(USERQUERY);
stmt.setString(1, username);
namers = stmt.executeQuery();
while (namers.next()) {
firstnameresult = namers.getString("firstname");
//results.add(namers.getString("firstname"))
catch (SQLException ex1) {
catch (ClassNotFoundException ex) {
finally {
if (stmt != null) {
try {
stmt.close();
catch (SQLException e) {
e.printStackTrace();
stmt = null;
if (con != null) {
try {
con.close();
catch (SQLException e) {
e.printStackTrace();
con = null;
//get the main links to pass on
try {
Class.forName(props.getProperty("connection.driver"));
con = DriverManager.getConnection(props.getProperty("connection.url"), props);
stmt = con.prepareStatement(MAINLINKQUERY);
mainlinkrs = stmt.executeQuery();
while (mainlinkrs.next()) {
mainlinkresults.add(mainlinkrs.getString("name"))
catch (SQLException ex1) {
catch (ClassNotFoundException ex) {
finally {
if (stmt != null) {
try {
stmt.close();
catch (SQLException e) {
e.printStackTrace();
stmt = null;
if (con != null) {
try {
con.close();
catch (SQLException e) {
e.printStackTrace();
con = null;
//get the announcements to pass on
try {
Class.forName(props.getProperty("connection.driver"));
con = DriverManager.getConnection(props.getProperty("connection.url"), props);
stmt = con.prepareStatement(ANOUNCEMENTQUERY);
anouncementrs = stmt.executeQuery();
while (anouncementrs.next()) {
anouncementresults.add(anouncementrs.getString("anouncement"));
catch (SQLException ex1) {
catch (ClassNotFoundException ex) {
finally {
if (stmt != null) {
try {
stmt.close();
catch (SQLException e) {
e.printStackTrace();
stmt = null;
if (con != null) {
try {
con.close();
catch (SQLException e) {
e.printStackTrace();
con = null;
request.setAttribute("firstname", firstnameresult);
request.setAttribute("mainlink", mainlinkresults);
request.setAttribute("anouncement", anouncementresults);
RequestDispatcher rd =
request.getRequestDispatcher("home.jsp");
rd.forward(request, response);
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public void destroy() {
JSP Page
<%@ taglib uri="http://java.sun.com/jstl/core" prefix="c" %>
<%@ taglib uri="http://java.sun.com/jstl/sql" prefix="sql" %>
<%@ taglib uri="http://java.sun.com/jstl/xml" prefix="x" %>
<html>
<head>
<title>
index
</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"><style type="text/css">

</style></head>
<body bgcolor="#008000">
<table width="100%" border="1" cellspacing="0" bordercolor="#000000">
<tr>
<td bgcolor="#FFFFFF"><h1>Welcome to NNET <c:out value="${requestScope.firstname}" /></h1>
</td>
</tr>
</table>
<br>
<table width="100%" border="0" cellspacing="0">
<tr>
<td width="150"><table width="100%" border="1" cellspacing="0" bordercolor="#000000" bgcolor="#FFFFFF">
<tr>
<td><strong>Main Links </strong></td>
</tr>
<c:forEach var="item" items="${requestScope.mainlink}">
<tr>
<td valign="top"><c:out value="${item}"/></td>
</tr>
</c:forEach>
</table>
<p> </p></td>
<td><table width="100%" border="0" cellspacing="0" bgcolor="#FFFFFF">
<tr>
<td valign="top"><h2>Announcements</h2>
<p>
<c:forEach var="item" items="${requestScope.anouncement}">
<c:out value="${item}" />
</c:forEach>
</p>
</td>
</tr>
</table></td>
<td width="150"> </td>
</tr>
</table>
</body>
</html>

OK if you look at the code I pasted above I have doen that. I hav ethat book and it is good. My question is how do I get the data read into a multidemisional array or an arraylist like I am using in the code above so I can access that on the jsp page. Can you give an example. Here is what I want . I have a table called anouncements with 3 fields (ID, name, url) I am returning say 10 results. I want to store them in a single arraylist or multideminsional array and call them on the jsp page. What syntax would I use on the servlet and on the jsp page for this? I know how to do it as seen above when I return only one field with many results from the database. Thank you in advance for any help

Beginner JSP / Forms question

Hello,
I'm just starting with jsps and I've got a pretty simple question. In my jsp I generate a form with two fields: age and weight. I'm wondering what the best method is for handling the users response. Two specific questions: (1) I'm currently handling the response in the same jsp which generates the form. Is this bad, uh, form? (2) To differentiate between the 'initial' request and the request resulting from the users form submission I'm arbitrarily checking whether the value of the 'age' parameter is null. Is there a better way to do that? Thanks in advance for any thoughts on these issues.
-exits

Yeah, that is fine for early JSPs (on both questions).
A couple of thoughts:
1) What if the user submits a weight but not an age? You should probably check if either of the two inputs are null.
2) This design is fine for smaller applications (it is called the Model 1 application design). For more complex applications, using Model 2 (Model - View - Controller or MVC) pattern is much better.
Basically you use a combination of Servlets and JSPs. One servlet is the target of all your links and forms - this is the Controller. Based on parameters and other conditions, the controller determines where the page should go next, and accesses the business logic (other classes that get/store data or calculates results. These other classes are the Model) , and passes this information to the the JSP needed to display that information (the View).
This helps JSPs stay small and manageable, since adding to much logic in a JSP means writing scriptlets, which become tough to maintain later on. It takes more work up front, but for larger apps and over longer periods of time (when it becomes time to update the look, or fix bugs) it makes a lot of sense.

Sample JSP interview question

I need some interview fresher level question on JSP,Servlet

hi
http://www.google.co.in/search?hl=en&client=firefox-a&rls=org.mozilla:en-US:official&hs=AxN&sa=X&oi=spell&resnum=0&ct=result&cd=1&q=interview+jsp+servlet+java+model+questions&spell=1

JSP/javascript question. Guru's please help.

Need help.
I know we can assign value of a JSP variable to a javascript variable. e.g. strJScriptvar = <%=strJSPvar%>;
Is there a way we can go the other way, i.e. assigning a javascript variable value to a JSP variable?
e.g. will it be valid <%strJSPvar=%>=strJScriptvar;
If not, is there a direct way of assigning the value.
Any help will be heavily appreciated.
Thanks,
Indrasish.

Yeah, that's it. Remember that JSPs are compiled into servlets then sent as HTML to your browser. Once the page is sent to your browser, there is nothing else the "JSP" part of it can do. It's already been processed, done it's thing, and sent the results to your browser.
Make sense?

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