Request.setHeader in servlet filter

Hi there,
I am working on servlet filter to filter HttpServletRequest before sending it to the original servlet.
The original servlet expects some content posted in the body of HttpServletRequest object.
In my servlet filter, I need to modify this content (already done) and then doFilter to the origin.
And here is the problem:
The original servlet uses HTTP header's content-length value to read the entire content posted. But if I modify this content in my filter, it will never get correct content of the request.
Unfortunately the original servlet is black boxed and there is no way to modify it.
Is there any way to modify HTTP headers of HttpServletRequest in servlet filter?
Thank you for any suggestions,
mato_v

Hum... ServletRequest.getHeader is read only, so you can't change them. There few solution you may try though:
* Try create another wrapper instance of ServletRequest inside your filter and forward it to your black box servlet. You might have to wrote your own implementation to manipulate those Headers.
* How about after you changed your data, redirect/post to your black box with the correct content? Use java.net.HttpURLConnection or a java Http client to do fancy posting if needed.
Hope these helps.

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Servlet Filter - Reading Request Error

I have a servlet filter that sits in front of a webservice servlet (AXIS) - what I want the filter to do is to look at the content of the ServletRequest and if a particular string is located in the request, I want to call another service. Everything works just fine except (isin't there always an execept) that when I execute the following code in the filter:
BufferedReader inReader = request.getReader();
String line = null;
StringBuffer sbuf = new StringBuffer();
// Read the current request into a buffer
while((line = inReader.readLine()) != null) {
sbuf.append(line);
sbuf.append("\n\r");
if (sbuf.toString().indexOf("mystring") > -1) {
// I do some code
} else {
chain.doFilter(request, wrapper);
When I execute this code, at the chain.doFilter I get an "java.lang.IllegalStateException: getReader() has already been called for this request"
I know that this is because I obtained the Reader from the request. But my question is - How can I look at the request string so that I can evaluate it and not have this exception thrown..
Thx in advance...

My guess is that when you do the chain.doFilter you pass the request to another resource that then tries to access the request.getInputStream method.
From the JavaDocs:
getReader
public java.io.BufferedReader getReader()
throws java.io.IOException
Retrieves the body of the request as character data using a BufferedReader. The reader translates the character data according to the character encoding used on the body. Either this method or getInputStream() may be called to read the body, not both.
Returns:
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import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
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     String timeoutPage = "SessionExpired.jsp";
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               //httpServletResponse.setHeader("Pragma","no-cache");
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The index.htm file (or the relevant portion)<HTML>
<Head>
<META http-equiv="Content-Style-Type" content="text/css">
<LINK href="RTEStyleSheet.css" rel="stylesheet" type="text/css">
<TITLE>Login</TITLE>
</HEAD>
<BODY>
<FORM NAME="Login" METHOD="POST" ACTION="rte.ServletLDAP">
<table width="100%" border="0" cellpadding="0" cellspacing="0">
     <tr>
          <td width="30%" align="left"><img src="images/top_logo_new2.gif">
          </td>
          <td width="37%" align="center"></td>
          <td width="33%" align="right"></td>
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</table>
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          <description>
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          <display-name>
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          <filter-class>SessionTimeoutFilter</filter-class>
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               <param-name>test-param</param-name>
               <param-value>this is a test parameter</param-value>
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          <url-pattern>/*</url-pattern>
          <dispatcher>REQUEST</dispatcher>
          <dispatcher>FORWARD</dispatcher>
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Hi,
Try adding CSS files and images to the excluded Pages.

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wynton_0 wrote:
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See here:
[http://wiki.apache.org/myfaces/AccessFacesContextFromServlet]
and here:
[how to access faces context and backing beans in a servlet filter|http://www.thoughtsabout.net/blog/archives/000033.html]
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836522 wrote:
I really cant thank everyone enough for your help, thank you :)
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ram.

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SSO2Ticket within servlet filter - Orionserver

Hi,
I need to validate user that already logged in via SAP portal.
So I get ticket as cookie.
I read this cookie and try to validate it with SSO2Ticket.java that is JNI wrapper for C application.
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It seams to load sapssoext.dll but what ever method I call I get:
java.lang.UnsatisfiedLinkError
Here is method that performs calls. Method is called from filter doFilter method.
There is SSO2Ticket.java attached here.
private void checkSAPTicket(HttpServletRequest request) throws Exception
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try
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checkSAPTicket
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ssf_library=C:\project\GSS\orion-2.0.2\sapsecu.dll
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static part ends.
java.lang.UnsatisfiedLinkError: getVersion
evalLogonTicket call ended...
Could not validate SAP login ticket from HTTP Header.
If I omit call SSO2Ticket.getVersion(); than the same exception is for SSO2Ticket.init(ssf_library).

Hi,
I think java.lang.UnsatisfiedLinkError means that it cannot find the .dll files.
I am not sure it will find them even if the are registered with regsvr32.
Have you tried placing the .dll files somewhere in the classpath ?
Dagfinn

Request.setHeader in servlet filter

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