>From the Flink documentation: Conditions for a class to be treated as a POJO by Flink:
- The class must be public - It must have a public constructor without arguments - All fields either have to be public or there must be getters and setters for all non-public fields. In your example, the zero argument constructor is missing. You could consider adding the constructor or changing to case classes. On Wed, Feb 11, 2015 at 10:08 AM, Fabian Hueske <fhue...@gmail.com> wrote: > In case you want to contribute or follow the discussion, here's the JIRA: > https://issues.apache.org/jira/browse/FLINK-1511 > > Again, thanks for reporting! > > 2015-02-11 9:59 GMT+01:00 Fabian Hueske <fhue...@gmail.com>: >> >> 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. >> >> >
