(This article was first published on Romain Francois, Professional R Enthusiast, and kindly contributed to R-bloggers)
Assuming rJava is installed and works, it is possible to take advantage of its magic to get the path where java is installed:
$ Rscript --default-packages="methods,rJava" -e ".jinit(); .jcall( 'java/lang/System', 'S', 'getProperty', 'java.home' ) " [1] "/opt/jdk/jre"
This is useful when you develop scripts that need to call a java program without assuming that java is on the path, or the JAVA_HOME environment variable is set, etc ...
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