Program: 112191
Project: 112191
Buggy source:
@Override public IBundleProvider invokeServer(IRestfulServer<?> theServer,RequestDetails theRequest,Object[] theMethodParams) throws InvalidRequestException, InternalErrorException {
  IIdType requestId=theRequest.getId();
  theMethodParams[myIdIndex]=ParameterUtil.convertIdToType(requestId,myIdParameterType);
  Object response=invokeServerMethod(theServer,theRequest,theMethodParams);
  IBundleProvider retVal=toResourceList(response);
  if (retVal.size() == 1) {
    List<IBaseResource> responseResources=retVal.getResources(0,1);
    IBaseResource responseResource=responseResources.get(0);
    if (theRequest.getServer().getETagSupport() == ETagSupportEnum.ENABLED) {
      String ifNoneMatch=theRequest.getHeader(Constants.HEADER_IF_NONE_MATCH_LC);
      if (StringUtils.isNotBlank(ifNoneMatch)) {
        ifNoneMatch=ParameterUtil.parseETagValue(ifNoneMatch);
        if (responseResource.getIdElement() != null && responseResource.getIdElement().hasVersionIdPart()) {
          if (responseResource.getIdElement().getVersionIdPart().equals(ifNoneMatch)) {
            ourLog.debug("String_Node_Str",Constants.HEADER_IF_NONE_MATCH,ifNoneMatch);
            throw new NotModifiedException("String_Node_Str");
          }
        }
      }
    }
    String ifModifiedSince=theRequest.getHeader(Constants.HEADER_IF_MODIFIED_SINCE_LC);
    if (isNotBlank(ifModifiedSince)) {
      Date ifModifiedSinceDate=DateUtils.parseDate(ifModifiedSince);
      Date lastModified=null;
      if (responseResource instanceof IResource) {
        InstantDt lastModifiedDt=ResourceMetadataKeyEnum.UPDATED.get((IResource)responseResource);
        if (lastModifiedDt != null) {
          lastModified=lastModifiedDt.getValue();
        }
      }
 else {
        lastModified=responseResource.getMeta().getLastUpdated();
      }
      if (lastModified != null && lastModified.getTime() > ifModifiedSinceDate.getTime()) {
        ourLog.debug("String_Node_Str");
        throw new NotModifiedException("String_Node_Str");
      }
    }
  }
  return retVal;
}

Fixed version (ground truth):
@Override public IBundleProvider invokeServer(IRestfulServer<?> theServer,RequestDetails theRequest,Object[] theMethodParams) throws InvalidRequestException, InternalErrorException {
  IIdType requestId=theRequest.getId();
  theMethodParams[myIdIndex]=ParameterUtil.convertIdToType(requestId,myIdParameterType);
  Object response=invokeServerMethod(theServer,theRequest,theMethodParams);
  IBundleProvider retVal=toResourceList(response);
  if (retVal.size() == 1) {
    List<IBaseResource> responseResources=retVal.getResources(0,1);
    IBaseResource responseResource=responseResources.get(0);
    if (theRequest.getServer().getETagSupport() == ETagSupportEnum.ENABLED) {
      String ifNoneMatch=theRequest.getHeader(Constants.HEADER_IF_NONE_MATCH_LC);
      if (StringUtils.isNotBlank(ifNoneMatch)) {
        ifNoneMatch=ParameterUtil.parseETagValue(ifNoneMatch);
        if (responseResource.getIdElement() != null && responseResource.getIdElement().hasVersionIdPart()) {
          if (responseResource.getIdElement().getVersionIdPart().equals(ifNoneMatch)) {
            ourLog.debug("String_Node_Str",Constants.HEADER_IF_NONE_MATCH,ifNoneMatch);
            throw new NotModifiedException("String_Node_Str");
          }
        }
      }
    }
    String ifModifiedSince=theRequest.getHeader(Constants.HEADER_IF_MODIFIED_SINCE_LC);
    if (isNotBlank(ifModifiedSince)) {
      Date ifModifiedSinceDate=DateUtils.parseDate(ifModifiedSince);
      Date lastModified=null;
      if (responseResource instanceof IResource) {
        InstantDt lastModifiedDt=ResourceMetadataKeyEnum.UPDATED.get((IResource)responseResource);
        if (lastModifiedDt != null) {
          lastModified=lastModifiedDt.getValue();
        }
      }
 else {
        lastModified=responseResource.getMeta().getLastUpdated();
      }
      if (lastModified != null && lastModified.getTime() <= ifModifiedSinceDate.getTime()) {
        ourLog.debug("String_Node_Str");
        throw new NotModifiedException("String_Node_Str");
      }
    }
  }
  return retVal;
}