simple scala program gives Error: java.lang.IncompatibleClassChangeError

Question

I'm using stanford's topic modelling toolkit

This is a simple scala program running on eclipse

Why do i keep getting this error Exception in thread "main" java.lang.IncompatibleClassChangeError: Implementing class

import scalanlp.io._;

object Main {
  def main(args: Array[String]) {

    println("added value"+c);

    val pubmed = CSVFile("pubmed-oa-subset.csv");

    println("Success: " + pubmed.data.size + " records");


  }
}

Full error here

Exception in thread "main" java.lang.IncompatibleClassChangeError: Implementing class
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
    at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
    at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
    at scalanlp.io.CSVFile$.CSVFileAsParcel(CSVFile.scala:73)
    at Main$.main(t1.scala:27)
    at Main.main(t1.scala)

Problem appears to be on `CSVFile.scala:73`, can you show that? — Danielson, Jul 23 '15 at 09:39
That is the input .csv file, dont know what you mean by "can you show `CSVFile.scala:73`" — wolfgang, Jul 23 '15 at 09:51
While Transferring RNA is interesting, I'll read it later... That's not what I meant, though. You are showing the Main class, which calls `CSVFile`, I suspect the problem is on the 73th line of `CSVFile` (the class) — Danielson, Jul 23 '15 at 09:53
@Danielson Apologies, I'm a scala newbie, here is the source code of that file https://searchcode.com/codesearch/view/1574270/ — wolfgang, Jul 23 '15 at 10:06
Take a look at this question http://stackoverflow.com/questions/1980452/what-causes-java-lang-incompatibleclasschangeerror — Dimitri, Jul 23 '15 at 10:22
@Danielson Hi Daniel, yes, my system has a small issue right now. i'll check and let you know very shortly :) — wolfgang, Jul 23 '15 at 12:32

score 1 · Accepted Answer · edited May 23 '17 at 12:14

1

The code supplied is correct... The problem is (most probably) a Scala version problem. The jar is compiled with Scala 2.8 (5 years ago), as quote from http://nlp.stanford.edu/software/tmt/tmt-0.4/:

TMT was written during 2009-10 in what is now a quite old version of Scala, using a linear algebra library that is also no longer developed. Some people still use it and find it a friendly piece of software for LDA and Labeled LDA models, and more power to you, but at this point we really can't offer any support or fix any problems. Sorry about that.

The IncompatibleClassChangeError as described here What causes java.lang.IncompatibleClassChangeError?, is due to a binary incompatibility. So the only option is to install an old version of Scala, preferable 2.8.0.

edited May 23 '17 at 12:14

Community

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answered Jul 23 '15 at 10:18

Danielson

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Thanks for looking into it Danielson, This is the modified program with the output http://pastebin.com/P40rgVEa – wolfgang Jul 23 '15 at 13:42
@Danierlson I'm running the latest Java SE7 Do you have any other ideas why i'm finding this error? library: http://nlp.stanford.edu/software/tmt/tmt-0.4/tmt-0.4.0.jar dataset http://nlp.stanford.edu/software/tmt/tmt-0.4/examples/pubmed-oa-subset.csv source code -> same as question – wolfgang Jul 23 '15 at 14:25
1

No, you didn't do anything wrong... I'm questioning Scala version... Since the project has been abandoned since 2010 (`TMT was written during 2009-10 in what is now a quite old version of Scala` from http://nlp.stanford.edu/software/tmt/tmt-0.4/) , a lot of things have been happened (without backwards compatibility support, which is why I returned to Java). I know some major stuff happened between 2.8.0 and 2.10... (I can't install Scala < 2.10 in Scala IDE...) – Danielson Jul 23 '15 at 15:12

simple scala program gives Error: java.lang.IncompatibleClassChangeError

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