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Mithrandir

[java] JSP's and POST

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Mithrandir    607
EDIT: I mean parameters, not attributes. I'm having a problem with my JSP's. For some reason, whenever I have a form that posts data, the post request is received, but there are absolutely no parameters with it.
<td width="44%">Existing Customers:
<table valign=top> <form method=post action="login.jsp"> <tr><td width="30%">Username:</td><td width="70%"><input type=text name="username"></td></tr>
<tr><td width="30%">Password:</td><td width="70%"><input type=password name="password"></td></tr></table>
<input type="image" src="login.jpg" name="action" value="login"> </td>
when the JSP gets parameter"action", there's nothing. In fact, when I enumerate any of the parameters, I get a null Enumeration class. Any ideas? [edited by - Mithrandir on April 28, 2003 4:11:57 PM]

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Guest Anonymous Poster   
Guest Anonymous Poster
Do you maybe want to use request.getParameter(name) instead of request.getAttribute(name) ? I know that''s what you would want to use to pull the username/password fields, but I''m not sure what you''re looking for out of the action parameter.

I use attributes of the session object all the time, but I still haven''t found a common use for request attributes (at least for form processing)...

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haggis22    122
If I put this at the top of what you provided and post to the same page...


<%@ page import="java.util.Enumeration" %>

<b><ul>Parameters
<%

Enumeration enum = request.getParameterNames();
String parm;
while (enum.hasMoreElements())
{
parm = (String)enum.nextElement();
out.print("<li>" + parm + "</li>");
}
%>
</ul></b>


I get a list showing username, password, action.x, and action.y - could you post a snippet of what you''re using that returns the nulls?

What if you include the parameters in the query string, like http://localhost:8080/login.jsp?action=go - does anything show up then?

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cwraith    122
Here''s a simple JSP I wrote which just creates a table displaying all the parameters passed to the page.


  
<%@ page import="java.util.*" %>

<!doctype html public "-//w3c//dtd html 4.0 transitional//en" "http://www.w3.org/TR/REC-html40/strict.dtd">

<head>
<title>Parameter echo demo</title>
</head>

<body>
<table border="1">
<tr>
<td width="200" align="center">
Name
</td>
<td width="200" align="center">
Value
</td>
</tr>
<%
Map m = request.getParameterMap();
for (Iterator i = m.entrySet().iterator(); i.hasNext(); )
{
Map.Entry e = (Map.Entry)i.next();
String name = (String)e.getKey();
String [] vals = (String [])e.getValue();
%>
<tr>
<td><%= name %></td>
<td>
<%
for (int j = 0; j < vals.length; j++)
{
%><%= vals[j] %><br><%
}
%>
</td>
</tr>
<%
}
%>
</table>
</body>
</html>

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