Question: how to install rjava in r?
Answer: Check whether R is 32/64 bit with sessionInfo() . ... 
Download the specific 32/64 bit of Java. ... 
Download Java JDK for 32/64 bit. ... 
If you installed 32-bit Java then everything should be saved in C:/Program Files (x86)/Java/ . ... 
Install rJava with install. ... 
Set your JAVA_HOME environment with Sys.