User macro generates excpetion on some invocations

Stephen Baxendale

The user macro show-ancestor-with-label (copy below) generates exceptions (eg, null pointer, array bounds, hibernate) but only on a small number of invocations.  It is intended to include a link to the first ancestor it finds with the given label.

Strangely rendering a page that calls the macro ~260 times is successful in approx. 2/3 tries, but on the failed case generates one of the exceptions.

Any suggestions on what may be driving the exceptions (some but not all of the time)?

## @Param Label:title=Label|type=string|required=true|desc=Pages that contain this label should be displayed

##set ( $ancestor = "" )
#foreach ( $ancestor in $content.getAncestors() )
  #foreach ( $label in $ancestor.getLabels() )
    #if ($label == $paramLabel)
      #contentLink2($ancestor, false, false)
      #break($foreach.parent)
    #end
  #end
#end

Stephen Baxendale

Thanks Bill Bailey, Changing from

# foreach ( $ancestor in $content.getAncestors() )  ** causes the semi-random exceptions **

to

#set( $currentPage = $pageManager.getPage($content.id) )
#foreach ( $ancestor in $currentPage.getAncestors() )

Has cleared up the exceptions !

Not sure exactly why, can only presume that the value of $content is somehow thread unsafe.

Thanks again for the tip Bill.