ASP.NET Page.ispostback equivalent in JSP/Java

Question

Is there any ASP.NET Page.IsPostback equivalent in JSP/Java? What I need to do is check whether this request is first time or is it result of post back. There are few Combo Boxes on JSP page and I need to load it only for the first time, (I am loading combo box's data from DB) not everytime page reloads. We reload the same page based on various input/selections etc. So I was looking for that type of method.

Answer 1

if ( "POST".equalsIgnoreCase(request.getMethod()) &&
   ((request.getRemoteURL() != null && 
      request.getRemoteURL().toString().equalsIgnoreCase("http://yoursite.com")) {

    //postback call 
}

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