in elitzur-avro/src/main/scala/com/spotify/elitzur/converters/avro/dynamic/dsl/AvroAccessorLogics.scala [58:65]
private def getNonNullSchema(schema: Schema): Schema = {
val nonNullSchemas: ju.ArrayList[Schema] = new ju.ArrayList[Schema]
schema.getTypes.forEach(s => if (s.getType != Schema.Type.NULL) {nonNullSchemas.add(s)})
if (nonNullSchemas.size > 1) {
throw new InvalidDynamicFieldException(INVALID_UNION_SCHEMA)
}
nonNullSchemas.get(0)
}