README.md

In petermeissner/javahelloworld: Minimal and Toy Example of some Java Code Packaged up for R

Minimal and Toy Example of some Java Code Packaged up for R

Status

lines of R code: 13, lines of test code: 0

Version

0.0.1 ( 2020-01-03 22:07:16 )

Description

A Package packaging up some Java code and allowing it to be called from R.

License

Apache License (>= 2.0) Peter Meissner [aut, cre]

Citation

citation("javahelloworld")

Meissner P (2020). javahelloworld: Minimal and Toy Example of some Java Code Packaged up for R. R package version 0.0.1.

BibTex for citing

toBibtex(citation("javahelloworld"))

@Manual{,
  title = {javahelloworld: Minimal and Toy Example of some Java Code Packaged up for R},
  author = {Peter Meissner},
  year = {2020},
  note = {R package version 0.0.1},
}

Installation

Stable version from CRAN:

install.packages("javahelloworld")

Usage

starting up

library(javahelloworld)

## Loading required package: rJava

calling Java?

test_method_call

## function(){
##     tmp <- rJava::.jnew("javahelloworld.App")
##     tmp$test_method()
##   }
## <bytecode: 0x00000000155cfdd0>
## <environment: namespace:javahelloworld>

let it run

test_method_call

## function(){
##     tmp <- rJava::.jnew("javahelloworld.App")
##     tmp$test_method()
##   }
## <bytecode: 0x00000000155cfdd0>
## <environment: namespace:javahelloworld>

How To Build an R/Java Package

• make R package
• install/use default maven (+ e.g. VSCode)
• add on.load function with rJava initialization to zzz.R file
• DESCRIPTION SystemRequirements: Java
• source: https://cran.r-project.org/web/packages/helloJavaWorld/index.html
• source: https://cran.r-project.org/web/packages/helloJavaWorld/vignettes/helloJavaWorld.pdf
• fix path and JAVA_HOME until package builds
• add package path to maven pom file
• add Java wrapper to R package
• ?Control Logging?:
  • https://docs.oracle.com/javase/7/docs/api/java/util/logging/LogManager.html
  • https://github.com/hrbrmstr/htmlunitjars/blob/master/R/logging.r

petermeissner/javahelloworld documentation built on Oct. 18, 2020, 8:35 p.m.