"illegal cyclic reference involving object InterfaceAudience" when using Scala 2.11 reflection

Question

I am hitting the above error on scala 2.11.7:

def main(args: Array[String]): Unit = {
  val x = typeOf[ org.apache.hadoop.io.Writable ]
  println( x )
}

Additional info of my compilation process:

I've narrowed to the bare minimum necessary to reproduce:

I have a project with a build.gradle like so:

buildscript {
  repositories {
      mavenCentral()
      maven {
        name 'Shadow'
        url 'http://dl.bintray.com/content/johnrengelman/gradle-    plugins'
      }
  }
  dependencies {
    classpath 'com.github.jengelman.gradle.plugins:shadow:1.2.1'
  }
}

apply plugin: 'com.github.johnrengelman.shadow'
apply plugin: 'scala'

repositories {
    mavenCentral()
}

dependencies 
{
  compile group: 'org.scala-lang', name: 'scala-library', version: '2.11.7'
  compile group: 'org.scala-lang', name: 'scala-reflect', version: '2.11.7'
  compile( "org.apache.hadoop:hadoop-common:2.4.0" )
}

This is my main:

import scala.reflect.runtime.universe._

object Test 
{
  def main(args: Array[String]): Unit = {
     val x = typeOf[ org.apache.hadoop.io.Writable ]
     println( x )
  }  
}

Building with:

gradle clean shadow

produces a jar with all dependencies.

java -cp ./build/libs/uber.jar Test

Results in the above exception

Does this problem present itself in the REPL also? Playing around on the 2.11.7 REPL the above works just fine. I have some ideas about what the error might be, but as I haven't been able to replicate it, I daren't say more. :) — Alec, Aug 23 '16 at 03:14
You are right, it works in REPL. Will try to investigate...many thanks! — Harel Gliksman, Aug 23 '16 at 10:51
When you get a chance, it might be useful to post your compilation process. I'm getting more and more curious about this. — Alec, Aug 23 '16 at 13:51

score 0 · Answer 1 · answered Jun 05 '18 at 04:19

0

Scala seems to fail upon reflecting on the Hadoop annotations, e.g. InterfaceAnnotations. The solution is to exclude the hadoop-annotations dependency:

configurations {
    all*.exclude group: 'org.apache.hadoop', module: 'hadoop-annotations'
}

answered Jun 05 '18 at 04:19

Eron Wright

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"illegal cyclic reference involving object InterfaceAudience" when using Scala 2.11 reflection

1 Answers1