I'm trying to call java code from R using the rJava package.
I need to pass a multidimensional (2d) doubles array to the java method and get back a 1d array of ints.
Here's the package information:
> sessionInfo()
R version 3.2.1 (2015-06-18)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 8 x64 (build 9200)
locale:
[1] LC_COLLATE=Portuguese_Brazil.1252 LC_CTYPE=Portuguese_Brazil.1252 LC_MONETARY=Portuguese_Brazil.1252
[4] LC_NUMERIC=C LC_TIME=Portuguese_Brazil.1252
attached base packages:
[1] stats graphics grDevices utils datasets methods base
other attached packages:
[1] rJava_0.9-6 RevoUtilsMath_3.2.1
loaded via a namespace (and not attached):
[1] tools_3.2.1
This is the code
Sys.setenv(JAVA_HOME="") # have to do this for rJava...
require(rJava)
.jinit()
.jaddClassPath("C:/Users/Cássio/Dropbox/workspace/snncluster/target/snncluster-0.0.1-SNAPSHOT-jar-with-dependencies.jar")
set.seed(1234)
Y1 = matrix(rnorm(30*2, mean = 0, sd = 1), 30, 2)
Y2 = matrix(rnorm(30*2, mean = 10, sd = 1), 30, 2)
Y3 = rbind(Y1, Y2)
#snn = .jnew("br/fapesp/snn/snncluster/SNN")
snn = J("br.fapesp.snn.snncluster.SNN")
#lbls = .jcall(snn, "[I", "snn", .jarray(Y3,'[[D'), 10, 5, 7, evalArray = TRUE)
lbls = snn$snn(.jarray(Y3, '[[D'), as.integer(10), as.double(5), as.integer(7))
I can't seem to determine the correct way to call the method.
jmethod returns:
> .jmethods(snn)
[1] "public static int br.fapesp.snn.snncluster.SNN.countIntersect(java.util.HashSet,java.util.HashSet)"
[2] "public static int[] br.fapesp.snn.snncluster.SNN.snn(double[][],int,double,int)"
[3] "public final void java.lang.Object.wait() throws java.lang.InterruptedException"
[4] "public final void java.lang.Object.wait(long,int) throws java.lang.InterruptedException"
[5] "public final native void java.lang.Object.wait(long) throws java.lang.InterruptedException"
[6] "public boolean java.lang.Object.equals(java.lang.Object)"
[7] "public java.lang.String java.lang.Object.toString()"
[8] "public native int java.lang.Object.hashCode()"
[9] "public final native java.lang.Class java.lang.Object.getClass()"
[10] "public final native void java.lang.Object.notify()"
[11] "public final native void java.lang.Object.notifyAll()"
I want to call the static method [2].
The return I get:
Error in .jcall("RJavaTools", "Ljava/lang/Object;", "invokeMethod", cl, :
java.lang.NoSuchMethodException: No suitable method for the given parameters
Any idea what is the correct way to call the method?
Thanks.
The correct (working) way would be
lbls = snn$snn(.jarray(Y3, dispatch = TRUE), as.integer(10), as.double(5), as.integer(7))
Thanks to S. Urbanek for the pointer.