Java related (?) problems with RWeka

Derek White whitedw at
Fri Mar 3 22:03:35 CET 2006

Hello all,

I am attempting to run an R script that makes use of RWeka.  I am
running SuSE Linux 9.3 with Java 1.5.0_06, R version 2.2.1, Weka
3-4-7, and Rweka 0.2-1.


I receive the error:

NewObject("weka/core/Instances","(Ljava/io/Reader;)V",...) failed
Exception in thread "main" end of line expected,
read Token[=], line 1
        at weka.core.Instances.errms(Unknown Source)
        at weka.core.Instances.getLastToken(Unknown Source)
        at weka.core.Instances.readHeader(Unknown Source)
        at weka.core.Instances.<init>(Unknown Source)
Error in validObject(.Object) : invalid class "jobjRef" object:
invalid object for slot "jobj" in class "jobjRef": got class "NULL",
should be or extend class "externalptr"
In addition: Warning message:
Unable to create object of the class weka/core/Instances , returning
null reference. in: .jnew("weka/core/Instances", .jcast(reader,
Execution halted

My R script seems to run fine on Windows XP.

Thanks in advance,

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