Using Factory pattern with browser back button bug

[asookazian]

We found a back button-related bug today in my Seam app that had to do with using @Factory with @DataModel to generate ListDataModel objects for my <rich:dataTable> components.

User would navigate to page A, click edit link in dataTable for a row, (now the @Factory methods fire for the dataTables in the next JSF page), click browser back button, click edit for a different row.

The use case is modeled using a LRC so all components (e.g. SFSB backing beans) are CONVERSATION-scoped.  So the bug was that we were seeing cached/stale data in the dataTables for the next page the 2nd time user clicks edit.

I solved this problem but am not sure it is the best way to solve it.  I added an init() method to the 2nd page's backing bean.  And added a call to that method in my pages.xml:

<page view-id="/RepairCaseDetails.xhtml">
         <description>Repair Case Details</description>
         <action execute="#{repairCaseDetails.init}"/> 
         <navigation>              
              <rule if-outcome="cancel">
                   <end-conversation before-redirect="true"/>
                   <redirect view-id="/ManageEquipment.xhtml"/>
              </rule>
         </navigation>
    </page>

NOTE: RepairCaseDetails.xhtml is the 2nd JSF page.

The complication was that I have rich:modalPanel components in the 2nd page and those were making the init() to be executed two times each during load/display phase (possibly due to reRendering as well?)

So then I added this in the 1st page's backing bean:

@Out(required=false)
     private Boolean doInitRepairCaseDetails;

public void processRepairHistorySelection()
     {     
          repairId = (Integer)repairHistorySelection[0];
          serialNumber = (String)repairHistorySelection[1];
          doInitRepairCaseDetails = true;
                    
          log.info("in processRepairHistorySelection(): repairId = " + repairId + "; serialNumber = " + serialNumber);
     }

processRepairHistorySelection() is the method that is executed when user clicks the edit link in 1st page's dataTable edit column.

Here is the init() method for 2nd page's backing bean:

//asookazi: set the @DataModel List instances to null so the @Factory methods will fire.
     //this addresses the following bug:      from ManageEquipment page, click edit link in repair history, then click browser back button,
     //then click edit for different row in repair history dataTable, you'll see cached data from previous repairId's dataTables in RepairCaseDetails page.
     public void init()
     {
          if (doInitRepairCaseDetails)
          {
               repairGeneralInfoList = null;               
               equipmentRepairFindingCodeList = null;               
               equipmentRepairProblemCodeList = null;          
               equipmentRepairCostList = null;
               totalCost = 0.00;
               cost = 0.00;
               doInitRepairCaseDetails = false;
          }
     }

So now the @Factory methods are only executed after user clicks the edit link, and not when the modalPanels display.

I have a feeling that this is not a good idea, but it does work:

@In(required=false)
     @Out(required=false)
     private Boolean doInitRepairCaseDetails;

Any comments/suggestions?