Site icon R-bloggers

How to load the {rJava} package after the error “JAVA_HOME cannot be determined from the Registry”

[This article was first published on R-statistics blog » RR-statistics blog, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here)
Want to share your content on R-bloggers? click here if you have a blog, or here if you don't.
< fb:like href='http://www.r-statistics.com/2012/08/how-to-load-the-rjava-package-after-the-error-java_home-cannot-be-determined-from-the-registry/' layout='default' show_faces='true' width='400' action='like' colorscheme='light' send='false' />

In case you tried loading a package that depends on the {rJava} package (by Simon Urbanek), you might came across the following error:

Loading required package: rJava
library(rJava)
Error : .onLoad failed in loadNamespace() for ‘rJava’, details:
call: fun(libname, pkgname)
error: JAVA_HOME cannot be determined from the Registry

The error tells us that there is no entry in the Registry that tells R where Java is located. It is most likely that Java was not installed (or that the registry is corrupt).

This error is often resolved by installing a Java version (i.e. 64-bit Java or 32-bit Java) that fits to the type of R version that you are using (i.e. 64-bit R or 32-bit R). This problem can easily effect Windows 7 users, since they might have installed a version of Java that is different than the version of R they are using.
You can pick the exact version of Java you wish to install from this link. If you might (for some reason) work on both versions of R, you can install both version of Java (Installing the “Java Runtime Environment” is probably good enough for your needs).
(Source: Uwe Ligges)

Other possible solutions is trying to re-install rJava.

If that doesn’t work, you could also manually set the directory of your Java location by setting it before loading the library:

Sys.setenv(JAVA_HOME='C:\\Program Files\\Java\\jre7') # for 64-bit version
Sys.setenv(JAVA_HOME='C:\\Program Files (x86)\\Java\\jre7') # for 32-bit version
library(rJava)

(Source: “nograpes” from Stackoverflow, which also describes the find.java in the rJava:::.onLoad function)

< fb:like href='http://www.r-statistics.com/2012/08/how-to-load-the-rjava-package-after-the-error-java_home-cannot-be-determined-from-the-registry/' layout='default' show_faces='true' width='400' action='like' colorscheme='light' send='false' />

To leave a comment for the author, please follow the link and comment on their blog: R-statistics blog » RR-statistics blog.

R-bloggers.com offers daily e-mail updates about R news and tutorials about learning R and many other topics. Click here if you're looking to post or find an R/data-science job.
Want to share your content on R-bloggers? click here if you have a blog, or here if you don't.