apache/spark — pull request #3273 by kai-zeng (2014-11-14 22:55:14+00:00)
Title: Added contains(key) to Metadata

Add contains(key) to org.apache.spark.sql.catalyst.util.Metadata to test the existence of a key. Otherwise, Class Metadata's get methods may throw NoSuchElement exception if the key does not exist.
Testcases are added to MetadataSuite as well.