GWT Upload is not working in cross domain request - gwt

Question

I am using GWTUplaod in my application which is working fine if I don't use cross domain.But it is not working correctly in cross domain scenario.
Let me explain,
GWT Server is at IP address 5.5.5.10 and GWT Client is at IP address 5.5.5.12 , earlier while uploading I was getting error in request due to cross domain then I override servlet doPost and doGetMethod
#Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
try {
FlowContextManager.getInstance().setFlowId(FlowContextManager.getNextFlowId());
processCrossDomainHeaders(request, response);
super.doGet(request, response);
} catch (Exception e) {
logger.error(e);
} finally {
FlowContextManager.getInstance().setFlowId("");
}
}
#Override
protected final void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException,
ServletException {
try {
FlowContextManager.getInstance().setFlowId(FlowContextManager.getNextFlowId());
processCrossDomainHeaders(request, response);
super.doPost(request, response);
} catch (Exception e) {
logger.error(e);
} finally {
FlowContextManager.getInstance().setFlowId("");
}
}
public void processCrossDomainHeaders(HttpServletRequest request, HttpServletResponse response) {
HttpServletResponse resp = response;
HttpServletRequest req = request;
String header = req.getHeader("Origin");
if (header != null) {
resp.addHeader("Access-Control-Allow-Origin", header);
}
resp.addHeader("Access-Control-Allow-Methods", "GET, POST, OPTIONS");
header = req.getHeader("Access-Control-Request-Headers");
if (header != null) {
resp.addHeader("Access-Control-Allow-Headers", header);
}
resp.addHeader("Access-Control-Max-Age", "100");
}
#Override
protected void doOptions(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
resp.addHeader("Access-Control-Allow-Origin", req.getHeader("Origin"));
resp.addHeader("Access-Control-Allow-Methods", "GET, POST, OPTIONS");
String header = req.getHeader("Access-Control-Request-Headers");
resp.addHeader("Access-Control-Allow-Headers", header);
resp.addHeader("Access-Control-Max-Age", "100");
super.doOptions(req, resp);
}
Now my GWTUploadServlet is extending this abstract servlet.
In my web.xml I have specified following entries
<servlet>
<servlet-name>uploadServlet</servlet-name>
<!-- This is the default servlet, it puts files in session -->
<servlet-class>com.drishti.ameyo.webclient.server.WebClientUploadServlet</servlet-class>
<init-param>
<param-name>corsDomainsRegex</param-name>
<param-value>.*</param-value>
</init-param>
</servlet>
I have referred following link
http://code.google.com/p/gwtupload/issues/detail?id=187
Request is getting successful but I am getting following error on browser console.
Blocked a frame with origin "http://10.10.10.192:8888" from accessing a frame with origin "http://10.10.10.250:8888". Protocols, domains, and ports must match. FormPanelImpl.java:32
onSubmitComplete: null SuperDevModeLogger.java:71
onSubmitComplete exception parsing response: SuperDevModeLogger.java:71
com.google.gwt.xml.client.impl.DOMParseException: Failed to parse: error on line 1 at column 1: Document is empty
at createStackTrace
at fillInStackTrace_1
at fillInStackTrace
at $fillInStackTrace
at Throwable_1
at Exception_1
at RuntimeException_1
at DOMException_1
at DOMParseException_0
at throwDOMParseException
at parseImpl_0
at $parse_3
at parse_3
at onSubmitComplete_0
at $dispatch_22
at dispatch_23
at dispatch
at dispatchEvent_1
I didn't get some good solution on it.Please help for it.