Problems when trying to load a package in R due to

问题:

When I type require(xlsx) in order to load the package xlsx in R, the following messages is shown:

> require(xlsx)
Loading required package: xlsx
Loading required package: xlsxjars
Loading required package: rJava
Error : .onLoad failed in loadNamespace() for 'rJava', details:
  call: fun(libname, pkgname)
  error: JAVA_HOME cannot be determined from the Registry
Failed with error:  ‘package ‘rJava’ could not be loaded’

I've also tried to load the rJava package manually but got this error message:

require(rJava)
Loading required package: rJava
Error : .onLoad failed in loadNamespace() for 'rJava', details:
  call: fun(libname, pkgname)
  error: No CurrentVersion entry in Software/JavaSoft registry! Try re-installing Java and make sure R and Java have matching architectures.

Do you have any suggestion on how to solve the problem?

回答1:

The reason is probably linked to the fact you are using a 64-bit OS and R version but do not have Java installed with the same architecture. What you have to do is to download Java 64-bit from this page: https://www.java.com/en/download/manual.jsp

After that just try to reload the xlsx package. You shouldn't need to re-start R.

回答2:

I had a similar problem what worked for me was to set JAVA_HOME. I tired it first in R:

Sys.setenv(JAVA_HOME = "C:/Program Files/Java/jdk1.8.0_101/")

And when it actually worked I set it in System Properties -> Advanced -> Environment Variables by adding a new System variable. I then restarted R/RStudio and everything worked.

回答3:

Its because either one of the Java versions(32 bit/64 bit) is missing from your computer. Try installing both the Jdks and run the code.
After installing the Jdks open R and type the code

system("java -version")

This will give you the version of Jdk installed. Then try loading the rJava package. This worked for me.

回答4:

I had a similar issue. It is caused due the dependent package 'rJava'. This problem can be overcome by re-directing the R to use a different JAVA_HOME.

if(Sys.getenv("JAVA_HOME")!=""){
    Sys.setenv(JAVA_HOME="")
}
library(rJava)

This worked for me.

回答5:

If you have this error in RStudio, use Lauren's environmental code above and change your R version to the 32 bit version in Tools, Global Options. There should be both 32bit and 64bit R options if you have a newer version. This will require a restart of R, and limit your memory options. Installing the 64 bit version of the jre won't be required though.

回答6:

Answer in link resolved my issue.

Before resolution, I tried by adding JAVA_HOME to windows environments. It resolved this error but created another issue. The solution in above link resolves this issue without creating additional issues.

回答7:

An alternative package that you can use is readxl. This package don't require external dependencies.

回答8:

If you have this issue with macOS, there is no easy way here :( Especially, when you want to use R3.4. I have been there already ;)

R 3.4, rJava, macOS and even more mess ;)

For R3.3 is't little bit easier (R3.3 was compiled using different compiler).

R, Java, rJava and macOS adventures

回答9:

I think I found the resolution as I had the same problem!

My fix was to install both 32 bit and 64 bit JRE (Java Runtime Environment) version 8 update 181.(I require 32 bit for another application, but your fix can well be just re-installing 64 bit on its own.)