Replace an NPE with an informative warning.
Replace an NPE with an informative warning.


git-svn-id: 4d48d1092ee340c9ada5711cdbe4355b138bc22b@383626 13f79535-47bb-0310-9956-ffa450edef68

awylie/hadoop,awylie/hadoop,awylie/hadoop,awylie/hadoop,awylie/hadoop,awylie/hadoop,awylie/hadoop,awylie/hadoop,awylie/hadoop,awylie/hadoop