HTMLUnit & Vaadin Testing

I have been trying to use HTMLUnit to automate Vaadin application testing. Here are list of little tricks that I have figured out:
1. debugId for Vaadin component need to be set such as
Button :
saveButton.setDebugId("DenormalizedProductFilterForm_save");
Select :
sl_fetchSize.setDebugId("DenormalizedProductFilterForm_sl_fetchSize");
2. We need to use waitForBackgroundJavaScriptStartingBefore method to wait for DOM components .
3. Sometimes, click() does not do the job. We need to use {e.click(); e.mouseDown(); e.mouseUp();} or {div.dblClick();} to simulate click.
Sample code

 package com.wapice.epid.test;  
 import java.io.IOException;  
 import java.io.Serializable;  
 import java.net.MalformedURLException;  
 import java.util.logging.Level;  
 import org.apache.commons.logging.LogFactory;  
 import org.junit.Before;  
 import org.junit.Test;  
 import com.gargoylesoftware.htmlunit.FailingHttpStatusCodeException;  
 import com.gargoylesoftware.htmlunit.WebClient;  
 import com.gargoylesoftware.htmlunit.html.HtmlDivision;  
 import com.gargoylesoftware.htmlunit.html.HtmlElement;  
 import com.gargoylesoftware.htmlunit.html.HtmlForm;  
 import com.gargoylesoftware.htmlunit.html.HtmlPage;  
 import com.gargoylesoftware.htmlunit.html.HtmlPasswordInput;  
 import com.gargoylesoftware.htmlunit.html.HtmlSubmitInput;  
 import com.gargoylesoftware.htmlunit.html.HtmlTextInput;  
 public class TestSearchProduct implements Serializable {  
      /**  
       *   
       */  
      private static final long serialVersionUID = 1L;  
      @Before  
      public void before() {  
           LogFactory.getFactory().setAttribute("org.apache.commons.logging.Log",  
                     "org.apache.commons.logging.impl.NoOpLog");  
           java.util.logging.Logger.getLogger("com.gargoylesoftware.htmlunit")  
                     .setLevel(Level.OFF);  
           java.util.logging.Logger.getLogger("org.apache.commons.httpclient")  
                     .setLevel(Level.OFF);  
      }  
      public void testWithStress() {  
      }  
      @Test  
      public void test() {  
           final WebClient webClient = new WebClient();  
           webClient.getOptions().setThrowExceptionOnScriptError(false);  
           webClient.getOptions().setCssEnabled(true);  
           webClient.getOptions().setJavaScriptEnabled(true);  
           HtmlPage page;  
           try {  
                System.out.println("Starting test");  
                page = webClient  
                          .getPage("http://localhost:1123/someapp/application/");  
                // login  
                {  
                     HtmlForm form = page.getFormByName("loginform");  
                     HtmlSubmitInput button = form.getInputByName("submitButton");  
                     HtmlTextInput userName = form.getInputByName("j_username");  
                     userName.setValueAttribute("jaacco");  
                     HtmlPasswordInput password = form.getInputByName("j_password");  
                     password.setValueAttribute("jaacco");  
                     button.click();  
                }  
                // search for product  
                {  
                     page = webClient  
                               .getPage("http://localhost:1123/someapp/application/#listdenormalizedproductview");  
                     webClient.waitForBackgroundJavaScriptStartingBefore(5000);  
                     //select from Select  
                     {  
                          HtmlDivision div = page  
                                    .getHtmlElementById("DenormalizedProductFilterForm_sl_fetchSize");  
                          for (HtmlElement e : div.getElementsByTagName("div")) {  
                               e.click();  
                          }  
                          webClient.waitForBackgroundJavaScriptStartingBefore(1000);  
                          div = page.getHtmlElementById("VAADIN_COMBOBOX_OPTIONLIST");  
                          for (HtmlElement e : div.getElementsByTagName("td")) {  
                               if (e.asText().contains("200")) {  
                                    e.click();  
                                    e.mouseDown();  
                                    e.mouseUp();  
                                    break;  
                               }  
                          }  
                          webClient.waitForBackgroundJavaScriptStartingBefore(1000);  
                     }  
                     //click button  
                     {  
                          HtmlDivision div = page  
                                    .getHtmlElementById("DenormalizedProductFilterForm_save");  
                          div.dblClick();  
                     }  
                     webClient.waitForBackgroundJavaScriptStartingBefore(10000);  
                }  
           } catch (FailingHttpStatusCodeException e) {  
                e.printStackTrace();  
           } catch (MalformedURLException e) {  
                e.printStackTrace();  
           } catch (IOException e) {  
                e.printStackTrace();  
           }  
           webClient.closeAllWindows();  
      }  
 }