Posted on by Vinny Panne

HTTP POST URLFetch Using The Low Level Java API

Here’s a code snippet demonstrating how to generate a POST request using the low level urlfetch API.

The variables post_url and post_data represent the request URL and the content of the POST as strings. The response from the urlfetch is stored in response_content . If the request was unsuccessful (the target server returned a non-200 HTTP status code) a RuntimeException will be thrown.

HTTPRequest request = new HTTPRequest(new URL(post_url), HTTPMethod.POST);
request.setHeader(new HTTPHeader("User-Agent", "Example Application"));
request.setPayload(post_data.getBytes("UTF-8"));
HTTPResponse response = URLFetchServiceFactory.getURLFetchService().fetch(request);
//If the response wasn't successful, throw an exception.
if (response.getResponseCode() != 200) {
    throw new RuntimeException("Response code was not 200: " + response.getResponseCode());
}
String response_content = new String(response.getContent());

Remember to import the URLFetch library:

import com.google.appengine.api.urlfetch.*;