I think that adding the Java enum support directly is the way to go; I'm trying to avoid hacking Avro reflection where I can. Here's the patch, building off of the enum PType support in Java Crunch:
https://issues.apache.org/jira/browse/CRUNCH-472 On Tue, Sep 30, 2014 at 5:14 AM, David Whiting <davidwhit...@gmail.com> wrote: > We have encountered a strange problem in our Scrunch code when attempting > to serialize Java enum types (as generated by Avro). > > Basically, if you create an Avro-schema with an enum-typed field, then a > Java enum class will be generated for that field. When you create a Scrunch > pipeline to use it, and use it within a compound type as an intermediate > value, it fails when spilling to disk because the ReflectDatumWriter cannot > instantiate the enum type. > > Inspecting the implicit PTypeH parameter passed to the offending function > (flatMap to a 4-tuple in this case), we see that it resolves to > quads(records[MyEnumType), strings, strings, strings). The records gets > implemented by the PTypeFamiliy (AvroTypeFamily in this case), which > delegates to containers and then reflects, which in tern delegates to the > Avro standard reflection stuff. I would expect this to have no problem with > an enum type, but for some reason it is trying to instantiate it instead of > using it as an enum. > > Is there some special case for Java enums missing in PTypeH, or have I > maybe done something else wrong somewhere? >
