CodeSOD: Widgety Gadgety Boo

Ancient Coder submits for our review the following migraine-inducer:

This was a bug report about a very minor issue, a little warning box was not popping up. Simple, I thought, and I estimated it would take an hour to fix. Little did I know that someone had already poked at this issue and made this amazing log entry. I spent about half an hour trying to understand this code before I backed away, slowly.

Are you ready for this one, guys? I mean, really ready? OK, here we go:

This problem is caused by BUGREP-92726, but it is more complex problem. Actually it is caused by this part of code:

ForgivingSuper.java:1435
int lastWidget = WebThread.getWidgetHistoryMgr().getPreviousWidgetId();
// BUGREP-53139 03/24/2014 gmp - check whether previous ErrorGadget is 337, if it is do not put up ErrorGadget 32
ErrorGadgetWidget prevErrorGadget = WebThread.getPartialWidgetMgr()!=null?WebThread.getPartialWidgetMgr().getPreviousErrorGadget():null;
if((lastWidget == IWidgetIds.PROGRAM_INFO_Widget && WebThread.getErrorGadgetManager().getErrorGadget32OverrideStatus()) || 
    (((currentErrorGadget != null && currentErrorGadget.getErrorGadgetNumber() == ErrorGadget337) || 
    (prevErrorGadget != null && prevErrorGadget.getErrorGadgetNumber() == ErrorGadget337))))
{
    // WebThread.getErrorGadgetManager().removeErrorGadget(ErrorGadget32);
    ErrorGadgetContext = new ErrorGadgetContext();
    ErrorGadgetContext.put(ErrorGadget337_DATA_SERVICE_EVENT, se);
    ErrorGadgetContext.put(ErrorGadget337_Defeat_OPTIONS, prevErrorGadget.getContext().get(ErrorGadget337_Defeat_OPTIONS));
    WebThread.getErrorGadgetManager().showErrorGadget(ErrorGadget337, ErrorGadgetContext);
    WebThread.getErrorGadgetManager().setErrorGadget32OverrideStatus(false);
} else {
    // BUGREP-64543 03/24/2014 gmp - show ErrorGadget 32 since it is not overridden by ErrorGadget 337
    ErrorGadgetContext.put(ErrorGadget32_DATA_SERVICE_EVENT, se);
    ErrorGadgetContext.put(ErrorGadget32_IS_BOOKED, WebThread.getSharedAlgorithms().isScheduledToShow(se));
    curErrorGadgetManager.showErrorGadget(ErrorGadget32, ErrorGadgetContext);
}

This part of code is patch applied for BUGREP-92726 and it solves problem describe there, but only partially. As it creates another problems:
1. When above patch code is applied and we steps of reproduce BUGREP-92726 + go to report from used in steps of reproduce of BUGREP-92726, then we still see ErrorGadget337 despite that we expect ErrorGadget32 (as we swapped to other DataEvent).
It is because we go into following condition of above code snippet:

(prevErrorGadget != null && prevErrorGadget.getErrorGadgetNumber() == ErrorGadget337)

2. This can cause another similar problems every time when prevErrorGadget was ErrorGadget337. I think that, the if statement from the above snippet should be as simple as:

if(WebThread.getErrorGadgetManager().getErrorGadget32OverrideStatus())
{
        .....
} else {
   .....
}

However in such situation we have another problems to solve:
1. WebThread.getErrorGadgetManager().getErrorGadget32OverrideStatus() is not properly set throughout the code. It should improved.
2. prevErrorGadget can be null => following issue will return NullPointerException(): ErrorGadgetContext.put(ErrorGadget337_Defeat_OPTIONS, prevErrorGadget.getContext().get(ErrorGadget337_Defeat_OPTIONS));
3. Even if prevErrorGadget is not null, there are situations where prevErrorGadget.getContext().get(ErrorGadget337_Defeat_OPTIONS) returns Boolean object instead of DefeatOption object.

It is when we reproducing this issue (BUGREP-47765). Then following exception is caught:

|Oct 22 11:22:04  java.lang.IllegalArgumentException: Failed to build ErrorGadget337: com.parent.mw.ca.dat.DefeatOption object is expected.
 Refer to the javadoc for ErrorGadgetConstants.ErrorGadget337_XXX for details. Object received: java.lang.Boolean       
|Oct 22 11:22:04      at com.parent.finagler.nestedobsoletestructure.ErrorGadget.ErrorGadgetTextBuilder.getObject (Unknown Source, bco=79)
|Oct 22 11:22:04      at com.parent.finagler.nestedobsoletestructure.ErrorGadget.ErrorGadgetTextBuilder.buildErrorGadgetText (Unknown Source, bco=16486)
|Oct 22 11:22:04      at com.parent.finagler.nestedobsoletestructure.ErrorGadget.ErrorGadgetBuilder.buildTextBlock (Unknown Source, bco=9)
|Oct 22 11:22:04      at com.parent.finagler.nestedobsoletestructure.ErrorGadget.ErrorGadgetBuilder.buildErrorGadget (Unknown Source, bco=112)
|Oct 22 11:22:04      at com.parent.finagler.nestedobsoletestructure.ErrorGadget.ErrorGadgetManager.buildErrorGadget (Unknown Source, bco=201)
|Oct 22 11:22:04      at com.parent.finagler.nestedobsoletestructure.ErrorGadget.ErrorGadgetManager.showErrorGadget (Unknown Source, bco=15)
|Oct 22 11:22:04      at com.parent.finagler.nestedobsoletestructure.SystemEventMgr.handleViewingProblems (Unknown Source, bco=3327)
|Oct 22 11:22:04      at com.parent.finagler.nestedobsoletestructure.SystemEventMgr.handleViewingProblems (Unknown Source, bco=6)
|Oct 22 11:22:04      at com.parent.finagler.nestedobsoletestructure.SystemEventMgr$MyServiceEventListener$1.run (Unknown Source, bco=16)
|Oct 22 11:22:04      at com.parent.finagler.nestedobsoletestructure.EventManager.invokeAndWait (Unknown Source, bco=41)
|Oct 22 11:22:04      at com.parent.finagler.nestedobsoletestructure.EventManager$2.run (Unknown Source, bco=8)
|Oct 22 11:22:04      at com.parent.finagler.nestedobsoletestructure.EventManager$TaskWrapper.run (Unknown Source, bco=53)
|Oct 22 11:22:04      at ceej.util.ThreadPoolEntry.run (Unknown Source, bco=55)

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