I had a little shock after loading the new findbugs plugin. Actually I didn't
think it was findbugs at first. I thought someone had deleted a project from the
system, but I saw that the project was in the correct directory and everything
seemed fine. I looked inside the logs and upon startup of Hudson I found:

WARNUNG: Failed to load C:\Documents and Settings\build\.hudson\jobs\Dynaconf
java.lang.InstantiationError: hudson.plugins.findbugs.util.model.AnnotationProvider
at sun.reflect.GeneratedSerializationConstructorAccessor41.newInstance(Unknown
Source)
at java.lang.reflect.Constructor.newInstance(Constructor.java:494)
at
com.thoughtworks.xstream.converters.reflection.Sun14ReflectionProvider.newInstance(Sun14ReflectionProvider.java:54)
[...shortened for clarity]

I looked for hudson.plugins.findbugs within the build.xml (result build files)
and found the following entry within several builds. Seems to be results from a
previous version of findbugs.

<hudson.plugins.findbugs.FindBugsResultAction>
<result>
<delta>11</delta>
<owner class="build" reference="../../../.."/>
<numberOfWarnings>11</numberOfWarnings>
<numberOfNewWarnings>11</numberOfNewWarnings>
<numberOfFixedWarnings>0</numberOfFixedWarnings>
<low>0</low>
<normal>7</normal>
<high>4</high>
</result>
<healthReportBuilder>
<healthy>10</healthy>
<unHealthy>999</unHealthy>
<isHealthEnabled>true</isHealthEnabled>
<reportName>FindBugs</reportName>
<itemName>warning</itemName>
<isThresholdEnabled>false</isThresholdEnabled>
<threshold>0</threshold>
</healthReportBuilder>
<owner class="build" reference="../../.."/>
</hudson.plugins.findbugs.FindBugsResultAction>

After commenting out this section from all previous builds (perhaps 30 builds)
and restarting Hudson, the missing projects were shown again.

I think this is a defect, since my project just doesn't load because of
incompatible data (read older data). I know the data is somehow important to
view the results, but here the data isn't ignored, but rather the project is
removed from display.

Is a migration on my part possible? Is this behavior correct (Hudson doesn't
load project) or should this behavior be handled otherwise (loads project, but
same result as commenting out). I set the priority low since there is a workaround.