我的 R Studio 版本是 4.0。我安装了 xlsx 包，但是当我需要使用它时，出现错误：
library(xlsx)
Unable to find any JVMs matching version "(null)".
No Java runtime present, try --request to install.
Error: package or namespace load failed for ‘xlsx’:
.onLoad failed in loadNamespace() for 'rJava', details:
call: fun(libname, pkgname)
error: JVM could not be found
In addition: Warning messages:
1: In system("/usr/libexec/java_home", intern = TRUE) :
running command '/usr/libexec/java_home' had status 1
2: In fun(libname, pkgname) :
Cannot find JVM library 'NA/lib/server/libjvm.dylib'
Install Java and/or check JAVA_HOME …