Spring-remoting SimpleHttpInvokerRequestExecutor retries request when it shouldn't

Question

I am investigating a quite strange problem. The project I'm working on uses Spring-remoting to invoke methods over http. From what I have gathered so far the following happens:

1. My client code executes a request to the server
2. The server starts handling the request, but is slow
3. 25-30 seconds later, a new request comes in to the server
4. The second request finishes, the client continues its processing
5. A while later, the first request get completed, but the client no longer cares

Since my client code executes only one request to the Spring remoting client, and the client continuous on after the second invocation it receives is completed, I can only conclude that this occurs somewhere in the Spring remoting client.

The client uses AbstractHttpInvokerRequestExecutor to make the actual http-invocation, and this in turn uses SimpleHttpInvokerRequestExecutor to make the request. But, from what I can read, this has no mechanism to retry the requests. So now I'm quite stuck.

Can anyone think of what might cause this behaviour? (I have tried to keep the question clean, but I have more details if needed.)

Answer 1

Just an idea to give you some direction, not necessarily a solution. Use a third party Http client (not one from Spring) to see if it changes a behavior. That might help you to see if it is SimpleHttpInvokerRequestExecutor that is "guilty" of re-try or something else. Here is a very simple 3d party HttpClient: Provided in MgntUtils Open source library (written by me). Very simple in use. Take a look at Javadoc. Library itself provided as Maven artifacts and on Git (including source code and Javadoc). All in all your code may look like this:

private static void testHttpClient() {
    HttpClient client = new HttpClient();
    client.setContentType("application/json");
    String content = null;
    try {
        content = client.sendHttpRequest("http://www.google.com/", HttpMethod.GET);
        //content holds the response. Do your logic here
    } catch (IOException e) {
        //Error Handling is here
        content = TextUtils.getStacktrace(e, false);
    }
}