Hive throws an NPE if hive-default.xml.

If you don't have hive-default.xml in your classpath, you get the following error when you try to show tables in the the hive shell:

hive> show tables;
FAILED: Error in metadata: java.lang.NullPointerException
FAILED: Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask

It would be a lot more useful to print message indicating that hive-default.xml. This problem will become mute if HIVE-1530 gets accepted.