Provides the client-side classes and interfaces for making HTTP requests and
processing the associated responses.
Most applications will be interested in the Request
, RequestBuilder
,
RequestCallback
and Response
classes.
Caveats
Same-Origin Security Policy
Modern web browsers restrict client-side scripts from accessing items outside
of their source origin. This means that a script loaded from
www.foo.com
cannot access
content from
www.bar.com
. For more details please see,
Same-Origin Security
Policy.
Pending Request Limit
Modern web browsers are limited to having only two HTTP requests outstanding at
any one time. If your server experiences an error that prevents it from sending
a response, it can tie up your outstanding requests. If you are concerned about
this, you can always set timeouts for the request via
setTimeoutMillis(int)
.
Required Module
Modules that use the classes and interfaces in this package should inherit
the
com.google.gwt.http.HTTP
module.
{@gwt.include com/google/gwt/examples/http/InheritsExample.gwt.xml}
Quick Howto's
How should I write a RequestCallback handler class?
The following code shows how a
RequestCallback
instance should be written.
{@example com.google.gwt.examples.http.client.RequestCallbackExample}
How do I make a GET request?
The following example demonstrates how to perform an HTTP GET request.
{@example com.google.gwt.examples.http.client.GetExample}
How do I make a POST request?
The following example demonstrates how to perform an HTTP POST request.
{@example com.google.gwt.examples.http.client.PostExample}
How do I use request timeouts?
The following example demonstrates how to use the timeout feature.
{@example com.google.gwt.examples.http.client.TimeoutExample}
How do I construct a string for use in a query or POST body?
The following example demonstrates how to build a x-www-form-urlencoded string that can be used as a query string or as the body of a POST request.
{@example com.google.gwt.examples.http.client.QueryAndFormDataExample}
How can I make a RequestBuilder
send a request other than GET or POST?
The following example demonstrates how to allow an HTTP request other than a GET or a POST to be made.
Beware: if you plan on supporting Safari, you cannot use this scheme.
{@example com.google.gwt.examples.http.client.RequestBuilderForAnyHTTPMethodTypeExample}