R rJava Error on Mac when loading xlsx library

Question

when I execute the following code on Mac, I got this

**> library(xlsx)**

Loading required package: rJava
Error: package or namespace load failed for ‘rJava’:
 .onLoad failed in loadNamespace() for 'rJava', details:
  call: dyn.load(file, DLLpath = DLLpath, ...)
  error: unable to load shared object '/Library/Frameworks/R.framework/Versions/3.4/Resources/library/rJava/libs/rJava.so':
  dlopen(/Library/Frameworks/R.framework/Versions/3.4/Resources/library/rJava/libs/rJava.so, 6): Library not loaded: @rpath/libjvm.dylib
  Referenced from: /Library/Frameworks/R.framework/Versions/3.4/Resources/library/rJava/libs/rJava.so
  Reason: image not found
Error: package ‘rJava’ could not be loaded

I saw some posts here that changes the directory of Java Home, but they are all in Windows system. I am wondering how can I fix this in a Mac environment?

Answer 1

Try this

1. If homebrew is not installed, install it from https://brew.sh/
2. Run this from terminal: brew cask install java
3. Reinstall rJava from R console

In general, and to avoid similar problems in the future, I suggest to follow my post to install R using homebrew http://pacha.hk/2017-07-12_r_and_python_via_homebrew.html

Doing that solves path problems and related stuff that can re-appear if later you want to use R database tools and related.