3 Replies Latest reply on Aug 24, 2009 2:24 PM by gorgorotom

    Correct behavior of the rendered attribute with a datatable

    charliepower76
    charliepower76 Jul 22, 2008 3:16 PM

      Let's take a look at this simple fragment of page : 


      <h:dataTable  value="#{projectList.resultList}" var="project" rendered=" #{projectList.resultCount > 0}">
    <h:column>
     <h:outputText value="#{project.manager}"/>
    </h:column>
</h:dataTable>



      The projectList variable is an EntityQuery object. Using some classes from this post (great tool to measure performance of your application by the way !), i found that some methods get called more than once for apparently no reason :


      
31.55389 ms7   EntityQuery.getResultCount()

8.847945 ms1   EntityQuery.getResultList()

5.13022 ms1   EntityQuery.validate()



      Maybe someone here has already experienced similar behavior with EntityQuery or EntityHome objects ? When you have a large view with many components using the rendered attribute and the same method gets called 100 times or more, it may be a problem...


      Thanks,


      Charles

        • 1. Re: Correct behavior of the rendered attribute with a datatable
          gorgorotom Aug 24, 2009 2:16 PM (in response to charliepower76)

          Hi, i experiment the same bug, and it's really bored...



                              <s:div style="float:left;margin:15px;" id="div1">
                              <s:link view="/admin/societie.xhtml"  border="0"
                                      id="bt1"  rendered="#{bean.canSomething()}" >
                                                                        
                                   <h:graphicImage value="/test.png"
                                        style="border:0px" />
                                   <h:outputText
                                        value="#{language.getText('accueil.societiesManagement')}"
                                        style="display:block;" />
                              </s:link>
                         </s:div>





               public boolean canSomething() {
          valueOfHell++;
          System.out.println("debut canSomething...."+valueOfHell);


          if (valueOfHell==2){
               System.out.println("je retourne FAUX");
               return false;
          }

          System.out.println("fin canSomething...."+valueOfHell);
          return true;
     }





          i declare valueOfHell in static way....my class in on scopetype equal scope.SESSION


          so why, i have 5 call of canSomething ?
          if i try 'to hack' and return true value if i'm on the second calling, no way



          it's really a big bug i guess, not acceptable for a framework like seam...i wanna a patch, i'm sure we're not alone in this case

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          • 2. Re: Correct behavior of the rendered attribute with a datatable
            gorgorotom Aug 24, 2009 2:21 PM (in response to charliepower76)

            on my console i have...




            13:55:53,177 INFO  debut canSomething....1
            13:55:53,177 INFO  fin canSomething....1
            13:55:53,178 INFO  debut canSomething....2
            13:55:53,178 INFO  fin canSomething....2
            13:55:53,178 INFO  je retourne FAUX
            13:55:53,180 INFO  debut canSomething....3
            13:55:53,180 INFO  fin canSomething....3
            13:55:53,181 INFO  debut canSomething....4
            13:55:53,181 INFO  fin canSomething....4





            SO, i never see something like that


            this pb occur a real performance problem in my application


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            • 3. Re: Correct behavior of the rendered attribute with a datatable
              gorgorotom Aug 24, 2009 2:24 PM (in response to charliepower76) 


              13:55:53,177 INFO  debut canManageSocieties....1
13:55:53,177 INFO   fin canManageSocieties....1
13:55:53,178 INFO   debut canManageSocieties....2
13:55:53,178 INFO   fin canManageSocieties....2
13:55:53,178 INFO   je retourne FAUX
13:55:53,180 INFO   debut canManageSocieties....3
13:55:53,180 INFO   fin canManageSocieties....3
13:55:53,181 INFO   debut canManageSocieties....4
13:55:53,181 INFO   fin canManageSocieties....4




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