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princehyderabad

asked on

Array Display

This the servlet which I hv to use and get all values displayed in JSP. This servlet give you the Array of UserList.

.....
HttpSession session = request.getSession();
            String name = (String) session.getAttribute(mm_userName);
            try {
                  MMUser [] users = getUsers(name);
                  request.setAttribute(mm_userList, users);
            } catch (MMFailedUserActionException e) {
                  throw new ServletException(e);
            }
....

I'm trying with this code in JSP: Can anyone help to get retriver and display.
<%
String str[] = getServletContext().getAttribute(MMServletConstants.PARAM_USER_LIST);
out.println(str); %>

out.println(java.util.Arrays.asList(str));

princehyderabad

ASKER

This the error:

incompatible types found : java.lang.Object
required: java.lang.String[]
String str[] = getServletContext().getAttribute(MMServletConstants.PARAM_USER_LIST);
^
1 error

sudhakar_koundinya

>>String str[] = getServletContext().getAttribute(MMServletConstants.PARAM_USER_LIST);

Should be

Object object = getServletContext().getAttribute(MMServletConstants.PARAM_USER_LIST);

OTHERWISE

if it is a String
String str =(String) getServletContext().getAttribute(MMServletConstants.PARAM_USER_LIST);

sudhakar_koundinya

Are u expecting to code something like this??

<%
String str =(String) getServletContext().getAttribute(MMServletConstants.PARAM_USER_LIST);
MMUsers[] users=(MMUsers[])request.getAttribute(str);
%>

princehyderabad

ASKER

Error
cannot resolve symbol symbol : class MMUsers

princehyderabad

ASKER

For your code this:
Object object = getServletContext().getAttribute(MMServletConstants.PARAM_USER_LIST);
out.println(object);

Output is: null

sudhakar_koundinya

Object object = request.getAttribute(MMServletConstants.PARAM_USER_LIST);
out.println(object);

princehyderabad

ASKER

Still Output is: null

sudhakar_koundinya

let me know how you are working with servlet and jsp??

princehyderabad

ASKER

This is my servlet which is talking to DB and getting userlist, now I want o get the userlist displays in JSP page. Plz send me jsp code for that.

      public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

            // extract request parameters
            HttpSession session = request.getSession();
            String name = (String) session.getAttribute(MMServletConstants.PARAM_USER_NAME);
            try {
                  MMUser [] users = getUsers(name);
                  request.setAttribute(MMServletConstants.PARAM_USER_LIST, users);
            } catch (MMFailedUserActionException e) {
                  throw new ServletException(e);
            }

sudhakar_koundinya

OK you need to do this

public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

// extract request parameters
HttpSession session = request.getSession();
String name = (String) session.getAttribute(MMServletConstants.PARAM_USER_NAME);
try {
MMUser [] users = getUsers(name);
session.setAttribute(MMServletConstants.PARAM_USER_LIST, users);

} catch (MMFailedUserActionException e) {
throw new ServletException(e);
}

<%
Object []object = session.getAttribute(MMServletConstants.PARAM_USER_LIST);

if(object!=null)
{
for(int i=0;i<object.length;i++)
{
out.println(object[i]);
}
}

%>

sudhakar_koundinya

or

Servlet
========

public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

// extract request parameters
HttpSession session = request.getSession();
String name = (String) session.getAttribute(MMServletConstants.PARAM_USER_NAME);
try {
MMUser [] users = getUsers(name);
request.setAttribute(MMServletConstants.PARAM_USER_LIST, users);
RequestDispatcher dispatcher;
            dispatcher = context.getRequestDispatcher(YourJSPPage);
            dispatcher.forward(req, res);

} catch (MMFailedUserActionException e) {
throw new ServletException(e);
}

JSP
=====

Comment from objects
Date: 08/20/2004 09:07AM IST
      Comment

out.println(java.util.Arrays.asList(str));

Comment from princehyderabad
Date: 08/20/2004 10:52PM IST
      Author Comment

This the error:

incompatible types found : java.lang.Object
required: java.lang.String[]
String str[] = getServletContext().getAttribute(MMServletConstants.PARAM_USER_LIST);
^
1 error

Comment from sudhakar_koundinya
Date: 08/21/2004 12:05AM IST
      Your Comment

>>String str[] = getServletContext().getAttribute(MMServletConstants.PARAM_USER_LIST);

Should be

Object object = getServletContext().getAttribute(MMServletConstants.PARAM_USER_LIST);

OTHERWISE

if it is a String
String str =(String) getServletContext().getAttribute(MMServletConstants.PARAM_USER_LIST);

Comment from sudhakar_koundinya
Date: 08/21/2004 12:08AM IST
      Your Comment

Are u expecting to code something like this??

<%
String str =(String) getServletContext().getAttribute(MMServletConstants.PARAM_USER_LIST);
MMUsers[] users=(MMUsers[])request.getAttribute(str);
%>

Comment from princehyderabad
Date: 08/21/2004 12:18AM IST
      Author Comment

Error
cannot resolve symbol symbol : class MMUsers

Comment from princehyderabad
Date: 08/21/2004 12:19AM IST
      Author Comment

For your code this:
Object object = getServletContext().getAttribute(MMServletConstants.PARAM_USER_LIST);
out.println(object);

Output is: null

Comment from sudhakar_koundinya
Date: 08/21/2004 01:05AM IST
      Your Comment

Object object = request.getAttribute(MMServletConstants.PARAM_USER_LIST);
out.println(object);

Comment from princehyderabad
Date: 08/21/2004 01:06AM IST
      Author Comment

Still Output is: null

Comment from sudhakar_koundinya
Date: 08/21/2004 01:38AM IST
      Your Comment

let me know how you are working with servlet and jsp??

Comment from princehyderabad
Date: 08/21/2004 03:34AM IST
      Author Comment

This is my servlet which is talking to DB and getting userlist, now I want o get the userlist displays in JSP page. Plz send me jsp code for that.

public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

// extract request parameters
HttpSession session = request.getSession();
String name = (String) session.getAttribute(MMServletConstants.PARAM_USER_NAME);
try {
MMUser [] users = getUsers(name);
request.setAttribute(MMServletConstants.PARAM_USER_LIST, users);
} catch (MMFailedUserActionException e) {
throw new ServletException(e);
}

Comment from sudhakar_koundinya
Date: 08/21/2004 03:44AM IST
      Your Comment

OK you need to do this

public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

// extract request parameters
HttpSession session = request.getSession();
String name = (String) session.getAttribute(MMServletConstants.PARAM_USER_NAME);
try {
MMUser [] users = getUsers(name);
session.setAttribute(MMServletConstants.PARAM_USER_LIST, users);

} catch (MMFailedUserActionException e) {
throw new ServletException(e);
}

<%
Object []object = session.getAttribute(MMServletConstants.PARAM_USER_LIST);

if(object!=null)
{
for(int i=0;i<object.length;i++)
{
out.println(object[i]);
}
}

%>

sudhakar_koundinya

OOPS

Ignore previous one

Solution 1

Servlet
========

public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

// extract request parameters
HttpSession session = request.getSession();
String name = (String) session.getAttribute(MMServletConstants.PARAM_USER_NAME);
try {
MMUser [] users = getUsers(name);
request.setAttribute(MMServletConstants.PARAM_USER_LIST, users);
RequestDispatcher dispatcher;
dispatcher = context.getRequestDispatcher(YourJSPPage);
dispatcher.forward(req, res);

} catch (MMFailedUserActionException e) {
throw new ServletException(e);
}

JSP
=====
<%
Object []object = request.getAttribute(MMServletConstants.PARAM_USER_LIST);

if(object!=null)
{
for(int i=0;i<object.length;i++)
{
out.println(object[i]);
}
}

%>

Solution 2

Servlet
========

public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

// extract request parameters
HttpSession session = request.getSession();
String name = (String) session.getAttribute(MMServletConstants.PARAM_USER_NAME);
try {
MMUser [] users = getUsers(name);
session.setAttribute(MMServletConstants.PARAM_USER_LIST, users);

} catch (MMFailedUserActionException e) {
throw new ServletException(e);
}

JSP
=====
<%
Object []object = session.getAttribute(MMServletConstants.PARAM_USER_LIST);

if(object!=null)
{
for(int i=0;i<object.length;i++)
{
out.println(object[i]);
}
}

%>

princehyderabad

ASKER

I did for Solution 2:

incompatible types found : java.lang.Object
required: java.lang.Object[] Object []object = session.getAttribute(MMServletConstants.PARAM_USER_LIST);
^
1 error

sudhakar_koundinya

It's my mistake

Type cast it

Object []object = (Object[])session.getAttribute(MMServletConstants.PARAM_USER_LIST);

sudhakar_koundinya

Even for

first solution

Object []object = (Object[])request.getAttribute(MMServletConstants.PARAM_USER_LIST);

BTW

Are u from India Hyderabad or Pakistan Hyderabad?? Just curious

sudhakar_koundinya

if that does not work

Here is a modified solution

Servlet
========

public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

// extract request parameters
HttpSession session = request.getSession();
String name = (String) session.getAttribute(MMServletConstants.PARAM_USER_NAME);
try {
MMUser [] users = getUsers(name);
session.setAttribute(MMServletConstants.PARAM_USER_LIST,java.util.Arrays.asList( users));

} catch (MMFailedUserActionException e) {
throw new ServletException(e);
}

JSP
=====
<%
Object []object =((java.util.List) session.getAttribute(MMServletConstants.PARAM_USER_LIST)).toArray();

if(object!=null)
{
for(int i=0;i<object.length;i++)
{
out.println(object[i]);
}
}

%>

princehyderabad

ASKER

I'm trying you solutions ...hold....

I'm from Hyderabad(India) ..

princehyderabad

ASKER

Black Ouput, when I tried to put System.out.println(object);
I got "null"

princehyderabad

ASKER

Oops I guess why its null, because its bascially not at all going calling servlet. Please help to solve here:

<%@ page import="com.mid.user.MMUser, com.mid.servlet.*" %> [will this not call the serlvet or include or make servlet run and get ouput]
<%@ page import="java.net.*, java.io.*"%>
<%@ page session="true" %>
<%
Object []object = (Object[])session.getAttribute(MMServletConstants.PARAM_USER_LIST);
System.out.println("Testing on Console: " + object);
if(object!=null)
{
for(int i=0;i<object.length;i++)
{
out.println(object[i]);
}
}
%>

princehyderabad

ASKER

I included the serlvet in the JSP
<jsp:include page="/admin/GetUsers" />

Outputs:
JSP Output: "com.mid.mm.user.MMUser@ffd553 "
Console Output: User List: [Lcom.midstream.mm.user.MMUser;@1685e30

princehyderabad

ASKER

what happen sudhakar ???

ASKER CERTIFIED SOLUTION

sudhakar_koundinya

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princehyderabad

ASKER

This is the OUTPUT:

com.mid.mm.user.MMUser@1f01b29
com.mid.mm.user.MMUser@8721bd
com.mid.mm.user.MMUser@1b81d4f

Its showing object.length =3 which is correct, but not displaying the proper values...

sudhakar_koundinya

can u post MMUsers class code??

princehyderabad

ASKER

Hey Sudhakar I got it, but now you help me how to do same in beans. I think using bean it would be more easy and small code.
Idea is here to display the ALL: username, password, fullname, role in the table format.

<jsp:include page="/admin/GetUsers" />
<%
MMUser []userlist = (MMUser[])session.getAttribute(MMServletConstants.PARAM_USER_LIST);
if(userlist!=null)
{
for(int i=0;i<userlist.length;i++)
{
out.println(userlist[i].getName());
out.println("<br>");
}
}
%>

rEGARDS

sudhakar_koundinya

Do you know custom tags??

if you know this becomes much easy for you

//import com.mid.mm.user.*;
import javax.servlet.jsp.JspTagException;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.tagext.SimpleTagSupport;
import javax.servlet.*;
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;

public class MMCustomTag extends SimpleTagSupport {
private String html = null;

public MMCustomTag() {
super();
}

public void setHtml(String name) {
this.html = name;
}
public void doTag() {
try {

PageContext context = (PageContext)getJspContext();
ServletRequest request=context.getRequest();
ServletResponse response=context.getResponse();
PrintWriter out=response.getWriter();
HttpSession session=context.getSession();

MMUser []userlist = (MMUser[])session.getAttribute(MMServletConstants.PARAM_USER_LIST);
if(userlist!=null)
{
for(int i=0;i<userlist.length;i++)
{
String name=userlist[i].getName();
String password=userlist[i].getPassword();
String role=userlist[i].getRole();
String _html=""+html;
html=html.replaceAll("MM::USER",name);
html=html.replaceAll("MM::PASS",password);
html=html.replaceAll("MM::ROLE",role);
out.println(html);
html=new String(_html);

}
}

} catch (Exception ex) {
ex.printStackTrace();
}
}
}

princehyderabad

ASKER

oops sudhakar, no just tell me how to do it in JSP using jsp:bean.

Reason is I have this biz logic class (servlet) which I have to make use. I didnt do that big logic class, somebody else worte I hv to use jsp and use that biz logic class.
Please just tell me hwo to do it using JSP bean:

Right now this code is working fine with correct output:
<jsp:include page="/admin/GetUsers" />
<%
MMUser []userlist = (MMUser[])session.getAttribute(MMServletConstants.PARAM_USER_LIST);
if(userlist!=null)
{
for(int i=0;i<userlist.length;i++)
{
out.println(userlist[i].getName());
out.println("<br>");
}
}
%>

getName(), getfullName, getPassword(), getRole() are the methods already defined just used them as I have used getName() in above code.

regards

sudhakar_koundinya

And in jsp code you must call that tag simply like this

<jsp:include page="/admin/GetUsers" />
<MMCustomTag html="<YOUR HTML TEMPLATE>" />

that's all

sudhakar_koundinya

no there is nothing to do with that third party codes

sudhakar_koundinya

and custom tags are much better than beans

princehyderabad

ASKER

Okay 2 questions:

1: <MMCustomTag html="<YOUR HTML TEMPLATE>" />

what should be "Your HTML Template". Please tell in deatil

2: If there is a servlet (business logic) which is there already which talk to DB and gets all values and store in MMUser so is it good idea again to write servlet(your custom tag) and again in JSP pass 2 lines code ? Also I wanna display in nice row & colomns that isnt a pain in servlet to code html, in JSP much easy correct ?
If I'm wrong plz explain me ? Why and When

Regards