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remove http headers from response using java/camel

I need to remove the below headers from response that I sent to 3rd party.
$WSIS:
$WSPR: HTTP/1.1
$WSRA:
$WSRH:
$WSSC: http
$WSSN:
$WSSP:
Authorization:
What would be the best way to remove the HTTP headers from the response in Java or camel? We are using WAS 8.5 server.

There isa removeHeaders / removeHeader you can use. The former takes a pattern where you can remove using a wildcard pattern, eg removeHeader("$W*")

These headers are added by the WebSphere Plugin and not by Camel. Using removeHeader seems to be the only solution. The same worked for me...surely a good workaround but definitely not a solution..

Java - send HTTP POST request without downloading all the content

Is it possible to send HTTP POST request to a webserver and retrieve just headers of response or read just few bytes of the body, so the rest won't be downloaded at all (so it won't consume traffic)? If yes, how?
I know that there is a HEAD method for this, but I need to achieve it by POST method .. well, I am not sure if I need the POST method, I just need to post the data. Maybe if the webserver isn't secured well enough (it doesn't check what method it's used - it's just directly access the post data), is it possible to send "post data" by HEAD request?

There is no built-in HTTP mechanism for this, and HTTP HEAD requests do not allow content in the body. If however you are the one writing the server code then anything is possible.
If this is the case, I would suggest a URL parameter that triggers this behavior. For example:
POST /myURL - This would return the whole response
POST /myURL?body=minimal - Returns the reduced size response that you are looking for.
And you would have to code your server method to construct and return the appropriate response based on the URL parameter.

How to disable Ajax caching?

I am having an issue with ajax caching, This was a problem in IE browser too but i fixed it by Writing the Following code.
response.setHeader("Cache-Control", "no-cache");
response.setHeader("expires","-1");
response.setHeader("pragma","no-cache");
But I see Safari4.0 on MAC is Caching the Ajax request(We have a requirment to support this). Fire Fox never a problem. Regarding this "Expire" i am setting it to -1, i see lot of places it is set 0 or some old date from past. Will it make a difference?

Send an extra parameter with your GET request that will never be the same, for example, the current timestamp. Something like:
url = url + '&nocache=' + new Date().getTime();
This will prevent caching.

First, a note on your Expires header. Your question doesn't specify what server framework you're using, so I'm not sure if this is applicable. However, it looks like you might be sending an invalid Expires header.
The RFC requires Expires to be a date, however you appear to be setting the header to a literal "-1". There are many frameworks that have an expires property on their HTTP response object that takes an int and automatically calculates a date that is that number of seconds from now.
Use a HTTP inspector to ensure that your server is sending a validly formatted date and not -1 in the Expires header.
You might try making your Cache-Control header more restrictive:
response.setHeader("Cache-Control", "private, no-cache, no-store, must-revalidate");
must-revalidate tells caches that they must obey any freshness information you give them. HTTP allows caches to serve stale representations under special conditions; by specifying this header, you’re telling the cache that you want it to strictly follow your rules. [1]

According to RFC 2616 section 9.5 about POST
Responses to this method are not cacheable, unless the response
includes appropriate Cache-Control or Expires header fields. However,
the 303 (See Other) response can be used to direct the user agent to
retrieve a cacheable resource.
So, the browser must not cache POST responses, unless the response specifies otherwise. In the same time, browsers may cache GET responses, unless the response specifies otherwise. So, for the requests that should not be cached, such as AJAX requests, POST is preferrable method.
If you, for any reason, don't want to use POSTs for AJAX, you should use the trick mentioned by minitech, it is in fact widely used to force browser to load current version of any resource.

is there any tool to simulate http requests in java

I am trying to simulate HTTP requests in Java with the URL class and the HttpURLConnection class, the GET requests are easy to simulate while some POST requests seem harder because most POST request need Cookie in the request header. Some cookies were set by the HTTP response in the Set-Cookie field and I can get them by the function provided by HttpURLConnection, but I found that other cookies may be set by JavaScript and I have no way to handle them, so I wonder is there any packaged tool to simulate HTTP requests in Java?

try Apache commons Httpclient:
http://hc.apache.org/httpclient-3.x/

Why do you need to generate HTTP requests? Do you want to perform some stress tests?
I'd advise using something like JMeter (you can find a brief tutorial here).
Hope this helps something, it's better to avoid reinventing the wheel (if you need something like this, but it wasn't clear for me from your question).

For the cookie set with Javascript, you could try to parse the HTTP response, extract the cookie information and set it for your next request
For example, lets say, the response has code which calls a setCookie() function (setCookie is user-defined javascript function),
...
//some javascript code
setCookie("username", "johndoe");
//some more javascript
...
then you would extract the line setCookie() and the parse it for the name and value

Sending GET & POST requests in Java or other without responses

Is it possible to make GET & POST requests in Java or another language such that you don't care about what is returned?
As in just sending the requests but not wanting to receive any responses?

Whether you care about the response or not, it will be sent. The HTTP protocol specifications say that it must be.
If you don't care about the response, your client could just close the connection immediately after sending the request. But the chances are that you do want to know that the request was processed (i.e. the response status) even if you don't want to look at the contents of the response message.
So maybe you could send the request and request body, and read the response status and then close the connection without reading the response body. However, this has a downside. It means that you can't reuse the HTTP connection to make further requests. The next request to the same server has to open a new connection.

You could use anynchronous HTTP requests if you don't care about the responses (that way your worker thread will not have to wait for the response to come back). See http://www.javaworld.com/javaworld/jw-03-2008/jw-03-asynchhttp.html for some details on Asynchronous/Synchronous HTTP queries in Java. Then you can control if the anychronous thread does or does not handle the response (or any failure flagged on the communication) - as long as there were no TCP level failures on the request the connection will still be opened.

You can't control whether or not the server returns a response. Your code is free to ignore any response it receives.

It's pretty hard to not get responses because they're part of the HTTP protocol. but you can certainly ignore the responses.