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How to forward a request to another server

Ian Moore

Joined: Jul 12, 2002
Posts: 4
I'm trying to write a servlet (on WebLogic) which will sit between legacy web applications (OAS) and users, such that users can make a request for the original application, the proxy intercepts this call (using an iPlanet plugin) and gets passed the original URL. This servlet should then forward the request to the legacy application after some security checks and setting up some variables.
Does anyone know how to forward the request on to these legacy applications which will reside on a different machine ??
Thanks in anticiaption
Ian Moore
Dave Vick
Ranch Hand

Joined: May 10, 2001
Posts: 3244
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Byron Estes
Ranch Hand

Joined: Feb 21, 2002
Posts: 313
The forward() method on the RequestDispatcher won't work because the resource must be relative to the servlets root context.
It sounds like to me you are going to need to do some work with the package that will allow you to generate HTTP connections, requests, etc. Basic stuff is pretty easy, but more advanced processing can get tricky.
I did a search and found the following...
Note: I do not have any experience with this open source offering, but it appears to have a forwarding mechanism that does what you want to do. Even if you don't use it, it may give you a leg up in designing your solution.

Byron Estes<br />Sun Certified Enterprise Architect<br />Senior Consulant<br />Blackwell Consulting Services<br />Chicago, IL<br /><a href="" target="_blank" rel="nofollow"></a>
sandy gupta
Ranch Hand

Joined: Jan 30, 2001
Posts: 228
I guess its just your luck that i happened to have the same kind of problem and needed to do a bulk http post to some server. I used the org.apache.commons.httpclient package for the same.
For your legacy app u can use the HTTPClient, HttpPost classes under this package and post the request there(Post/Get Methods are available)
The problem here is reading the response from the legacy appln and then processing that to give the desired output. Seems like a lot of work but thats what u do with legacy app integration
Lemme know if u need the source code or more input

Ian Moore

Joined: Jul 12, 2002
Posts: 4
Byron, Sandy
Thanks for your replies, time to cut some code and see what happens !
Ian aka chinnermoore
I agree. Here's the link:
subject: How to forward a request to another server
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