Hi, you are right, there is a problem. I reproduced the problem and it seems that regular Scala classes are not properly analyzed and not identified as Pojos. As long as you only need these classes to be data holders without custom logic, you could go with case classes.
I will open a JIRA to extend Pojo support for regular Scala classes. Thanks for reporting, Fabian 2015-02-11 2:42 GMT+01:00 Vinh June <hoangthevinh....@gmail.com>: > sorry, here is also the Metadata class that I use > http://pastebin.com/WUQE613E > > > > -- > View this message in context: > http://apache-flink-incubator-user-mailing-list-archive.2336050.n4.nabble.com/Exception-Key-expressions-are-only-supported-on-POJO-types-and-Tuples-tp720p721.html > Sent from the Apache Flink (Incubator) User Mailing List archive. mailing > list archive at Nabble.com. >
