Rserve与Java的跨平台通信

R语言作为统计学一门语言，一直在小众领域闪耀着光芒。直到大数据的爆发，R语言变成了一门炙手可热的数据分析的利器。随着越来越多的工程背景的人的加入，R语言的社区在迅速扩大成长。现在已不仅仅是统计领域，教育，银行，电商，互联网….都在使用R语言。

要成为有理想的极客，我们不能停留在语法上，要掌握牢固的数学，概率，统计知识，同时还要有创新精神，把R语言发挥到各个领域。让我们一起动起来吧，开始R的极客理想。

关于作者：

• 张丹(Conan), 程序员Java,R,PHP,Javascript
• weibo：@Conan_Z
• blog: http://blog.fens.me
• email: bsspirit@gmail.com

转载请注明出处：
http://blog.fens.me/r-rserve-java/

前言

现在主流的异构跨平台通信组件Apache Thrift已经火遍大江南北，支持15种编程语言，但是到目前为止还没有加入R语言。要让R实现跨平台的通信，就只能从R的社区中找方案，像rJava,RCpp,rpy都是2种语言结合的方案，这些方案类似地会把R引擎加载到其他的语言内存环境。优点是高效，缺点是紧耦合，扩展受限，接口程序无法重用。

Rserve给了我们一种新的选择，抽象R语言网络接口，基于TCP/IP协议实现与多语言之间的通信。让我们体验一下Rserve与Java的跨平台通信。

目录

1. Rserve介绍
2. Rserve安装
3. Java远程连接Rserve

1. Rserve介绍

Rserve是一个基于TCP/IP协议的，允许R语言与其他语言通信的C/S结构的程序，支持C/C++,Java,PHP,Python,Ruby,Nodejs等。 Rserve提供远程连接，认证，文件传输等功能。我们可以设计R做为后台服务，处理统计建模，数据分析，绘图等的任务。

2. Rserve安装

系统环境:
Linux Ubuntu 12.04.2 LTS 64bit server
R 3.0.1 64bit

~ uname -a
Linux conan 3.5.0-23-generic #35~precise1-Ubuntu SMP Fri Jan 25 17:13:26 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux

~ cat /etc/issue
Ubuntu 12.04.2 LTS \n \l

~ R --version
R version 3.0.1 (2013-05-16) -- "Good Sport"
Copyright (C) 2013 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under the terms of the
GNU General Public License versions 2 or 3.
For more information about these matters see

http://www.gnu.org/licenses/.

Rserve安装

#建议使用root权限安装
~ sudo R

> install.packages("Rserve")
installing via 'install.libs.R' to /usr/local/lib/R/site-library/Rserve
** R
** inst
** preparing package for lazy loading
** help
*** installing help indices
** building package indices
** testing if installed package can be loaded
* DONE (Rserve)

启动Rserve

~ R CMD Rserve

R version 3.0.1 (2013-05-16) -- "Good Sport"
Copyright (C) 2013 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

  Natural language support but running in an English locale

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

Rserv started in daemon mode.

#查看进程
~ ps -aux|grep Rserve
conan     7142  0.0  1.2 116296 25240 ?        Ss   09:13   0:00 /usr/lib/R/bin/Rserve

#查看端口
~ netstat -nltp|grep Rserve
tcp        0      0 127.0.0.1:6311          0.0.0.0:*               LISTEN      7142/Rserve

这时Rserve已经启动，端口是6311。接下来，我们来简单地用一下。

Java远程连接Rserve

1). 远程连接Rserve
刚刚启动时，使用的本地模式，如果想运程连接需要增加参数 –RS-enable-remote

#杀掉刚才的Rserve守护进程
~ kill -9 7142

#打开远程模式重新启动
~ R CMD Rserve --RS-enable-remote

#查看端口
~ netstat -nltp|grep Rserve
tcp        0      0 0.0.0.0:6311            0.0.0.0:*               LISTEN      7173/Rserve

0 0.0.0.0:6311，表示不限IP访问了。

2). 下载Java客户端JAR包
下载Java客户端JAR包：http://www.rforge.net/Rserve/files/

• REngine.jar
• RserveEngine.jar

3). 创建Java工程
在Eclipse中新建Java工程，并加载JAR包环境中。

4). Java编程实现

package org.conan.r.rserve;

import org.rosuda.REngine.REXP;
import org.rosuda.REngine.REXPMismatchException;
import org.rosuda.REngine.Rserve.RConnection;
import org.rosuda.REngine.Rserve.RserveException;

public class Demo1 {

    public static void main(String[] args) throws RserveException, REXPMismatchException {
        Demo1 demo = new Demo1();
        demo.callRserve();
    }

    public void callRserve() throws RserveException, REXPMismatchException {
        RConnection c = new RConnection("192.168.1.201");
        REXP x = c.eval("R.version.string");
        System.out.println(x.asString());//打印变量x

        double[] arr = c.eval("rnorm(10)").asDoubles();
        for (double a : arr) {//循环打印变量arr
            System.out.print(a + ",");
        }
    }
}

5). 运行结果

R version 3.0.1 (2013-05-16)
1.7695224124757984,-0.29753038160770323,0.26596993631142246,1.4027325257239547,-0.30663565983302676,-0.17594309812158912,0.10071253841443684,0.9365455161259986,0.11272119436439701,0.5766373030674361,

通过Rserve非常简单地实现了，Java和R的通信。
解决了通信的问题，我们就可以发挥想象，把R更广泛的用起来。

接下来，会讲到如何设计Java和R互相调用的软件架构。

在巨人的肩膀前行 催化R包开发

R语言作为统计学一门语言，一直在小众领域闪耀着光芒。直到大数据的爆发，R语言变成了一门炙手可热的数据分析的利器。随着越来越多的工程背景的人的加入，R语言的社区在迅速扩大成长。现在已不仅仅是统计领域，教育，银行，电商，互联网….都在使用R语言。

要成为有理想的极客，我们不能停留在语法上，要掌握牢固的数学，概率，统计知识，同时还要有创新精神，把R语言发挥到各个领域。让我们一起动起来吧，开始R的极客理想。

关于作者：

• 张丹(Conan), 程序员Java,R,PHP,Javascript
• weibo：@Conan_Z
• blog: http://blog.fens.me
• email: bsspirit@gmail.com

转载请注明出处：
http://blog.fens.me/r-package-faster/

前言

在 开发自己的R包sayHello 一文中，我们看到了如何从底层，按照R语言的标准构建一个R语言的扩展包。但实施过程确实复杂，会让很多的统计学工作者望而却步。如果能有一种比较简单方式，简化开发过程，那该多好啊！

我们是幸运的，Hadley Wickham(ggplot2,plyr的作者)已经帮我们梳理出了一套开发流程。站在巨人的肩膀上，看得更高，走得更远。

目录

1. 开发流程介绍
2. 编写功能代码
3. 调试程序
4. 单元测试
5. 撰写文档
6. 程序打包
7. 程序发布

1. 开发流程介绍

站在巨人的肩膀，开发R包我们有3个武器：devtools, roxygen2, testthat

• devtools：让开发变得简单，各种开发小工具的合集，非常实用。
• roxygen2：通过注释的方式，生成文档，远离Latex的烦恼。
• testthat：单元测试，让R包稳定、健壮，减少升级的痛苦。

标准化的开发流程：

1. 编写功能代码
2. 调试程序
3. 单元测试
4. 撰写文档
5. 程序打包

2. 编写功能代码

1). 安装程序包：devtools, roxygen2, testthat

#依赖库
~ sudo apt-get install libcurl4-openssl-dev

#请使用root权限启动R
~ sudo R

> install.packages("devtools")
> install.packages("roxygen2")
> install.packages("testthat")

> library(devtools)
> library(roxygen2)
> library(testthat)

#查看
> search()
 [1] ".GlobalEnv"        "package:testthat"  "package:roxygen2"
 [4] "package:digest"    "package:stats"     "package:graphics"
 [7] "package:grDevices" "package:utils"     "package:datasets"
[10] "package:methods"   "Autoloads"         "package:base"

构建工程chinaWeather
创建骨架,代替package.skeleton()

> setwd("/home/conan/R")

> create("/home/conan/R/chinaWeather")
Creating package chinaWeather in /home/conan/R
No DESCRIPTION found. Creating default:

Package: chinaWeather
Title:
Description:
Version: 0.1
Authors@R: # getOptions('devtools.desc.author')
Depends: R (>= 3.0.1)
License: # getOptions('devtools.desc.license')
LazyData: true

> setwd("/home/conan/R/chinaWeather")
> dir()
[1] "DESCRIPTION" "man"         "R"

编辑DESCRIPTION文件

~ vi /home/conan/R/chinaWeather/DESCRIPTION
Package: chinaWeather
Type: Package
Title: a visualized package for china Weather
Description: a visualized package for china Weather
Author: Dan Zhang
Maintainer: Dan Zhang
Version: 0.1
Depends: R (>= 3.0.1)
License: GPL-2
LazyData: true
Date: 2013-08-05

增加函数文件chinaWeather.R

~ vi /home/conan/R/chinaWeather/R/chinaWeather.R

#define a filename from current date
filename<-function(date=Sys.time()){
  paste(format(date, "%Y%m%d"),".csv",sep="")
}

3. 调试程序

加载程序包到R中

> load_all("/home/conan/R/chinaWeather")
Loading chinaWeather

> filename
function(date=Sys.time()){
  paste(format(date, "%Y%m%d"),".csv",sep="")
}


> filename()
[1] "20130805.csv"

> day<-as.Date("20110701",format="%Y%m%d")
> filename(day)
[1] "20110701.csv"

4. 单元测试

编写单元测试代码

~ mkdir /home/conan/R/chinaWeather/inst/tests
~ vi /home/conan/R/chinaWeather/inst/tests/test.chinaWeather.R

library(testthat)
context("filename: current of date")

test_that("filename is current of date", {
  daystr<-paste(format(Sys.Date(), "%Y%m%d"),".csv",sep="")
  expect_that(filename(), equals(daystr))

  day<-as.Date("20110701",format="%Y%m%d")
  expect_that(filename(day), equals("20110701.csv"))
})

运行单元测试

#单个文件的单元测试
> source("/home/conan/R/chinaWeather/inst/tests/test.chinaWeather.R")
> test_file("/home/conan/R/chinaWeather/inst/tests/test.chinaWeather.R")
filename: current of date : ..

#对目录下所有文件的单元测试
> test_dir("/home/conan/R/chinaWeather/inst/tests/",reporter = "summary")
filename: current of date : ..

#自动单元测试
> src<-"/home/conan/R/chinaWeather/R/"
> test<-"/home/conan/R/chinaWeather/inst/tests/"
> auto_test(src,test)
filename: current of date : ..

#对package执行测试
> test("/home/conan/R/chinaWeather")
Testing chinaWeather
Loading chinaWeather
filename: current of date : ..

完成单元测试！下面开始撰写文档。

5. 撰写文档

这里撰写文档，使用源代码注释的方式，然后生成latex，再生成doc。比起原始的直接写latex要容易的多。

打开源代码文件：chinaWeather.R

~ vi /home/conan/R/chinaWeather/R/chinaWeather.R

#' Define a filename from current date.
#'
#' @param date input a date type
#' @return character a file name
#' @keywords filename 
#' @export
#' @examples
#' filename()
#' filename(as.Date("20110701",format="%Y%m%d"))
filename<-function(date=Sys.time()){
  paste(format(date, "%Y%m%d"),".csv",sep="")
}

生成latex文档

> library(roxygen2)
Loading required package: digest

> roxygenize("/home/conan/R/chinaWeather")
Updating collate directive in  /home/conan/R/chinaWeather/DESCRIPTION
Updating namespace directives
Writing chinaWeather.Rd
Writing filename.Rd

查看生成的latex文件

~ cat /home/conan/R/chinaWeather/man/filename.Rd

\name{filename}
\alias{filename}
\title{Define a filename from current date.}
\usage{
  filename(date = Sys.time())
}
\arguments{
  \item{date}{input a date type}
}
\value{
  character a file name
}
\description{
  Define a filename from current date.
}
\examples{
filename()
filename(as.Date("20110701",format="\%Y\%m\%d"))
}
\keyword{filename}

6. 程序打包

详细的打包解释，请参考：开发自己的R包sayHello

对上面程序过程，更简化操作可以用如下3条命令

> load_all("/home/conan/R/chinaWeather")
> test("/home/conan/R/chinaWeather")
> document("/home/conan/R/chinaWeather")

程序检查

> check("/home/conan/R/chinaWeather")
Updating chinaWeather documentation
Loading chinaWeather
'/usr/lib/R/bin/R' --vanilla CMD build '/home/conan/R/chinaWeather'  \
  --no-manual --no-resave-data

* checking for file '/home/conan/R/chinaWeather/DESCRIPTION' ... OK
* preparing 'chinaWeather':
* checking DESCRIPTION meta-information ... OK
* checking for LF line-endings in source and make files
* checking for empty or unneeded directories
* building 'chinaWeather_0.1.tar.gz'

'/usr/lib/R/bin/R' --vanilla CMD check  \
  '/tmp/RtmpM5NdJp/chinaWeather_0.1.tar.gz' --timings

* using log directory '/tmp/RtmpM5NdJp/chinaWeather.Rcheck'
* using R version 3.0.1 (2013-05-16)
* using platform: x86_64-pc-linux-gnu (64-bit)
* using session charset: ASCII
* checking for file 'chinaWeather/DESCRIPTION' ... OK
* checking extension type ... Package
* this is package 'chinaWeather' version '0.1'
* checking package namespace information ... OK
* checking package dependencies ... OK
* checking if this is a source package ... OK
* checking if there is a namespace ... OK
* checking for executable files ... OK
* checking for hidden files and directories ... OK
* checking for portable file names ... OK
* checking for sufficient/correct file permissions ... OK
* checking whether package 'chinaWeather' can be installed ... OK
* checking installed package size ... OK
* checking package directory ... OK
* checking DESCRIPTION meta-information ... OK
* checking top-level files ... OK
* checking for left-over files ... OK
* checking index information ... OK
* checking package subdirectories ... OK
* checking R files for non-ASCII characters ... OK
* checking R files for syntax errors ... OK
* checking whether the package can be loaded ... OK
* checking whether the package can be loaded with stated dependencies ... OK
* checking whether the package can be unloaded cleanly ... OK
* checking whether the namespace can be loaded with stated dependencies ... OK
* checking whether the namespace can be unloaded cleanly ... OK
* checking loading without being on the library search path ... OK
* checking for unstated dependencies in R code ... OK
* checking S3 generic/method consistency ... OK
* checking replacement functions ... OK
* checking foreign function calls ... OK
* checking R code for possible problems ... OK
* checking Rd files ... OK
* checking Rd metadata ... OK
* checking Rd cross-references ... OK
* checking for missing documentation entries ... OK
* checking for code/documentation mismatches ... OK
* checking Rd \usage sections ... OK
* checking Rd contents ... OK
* checking for unstated dependencies in examples ... OK
* checking examples ... OK
* checking PDF version of manual ... OK

Checking chinaWeather with devtools
Checking for any extra files in built .tar.gz file... OK

查检通过.
注：请安装

sudo apt-get install texlive-full

7. 程序发布

我们把写的程序发布到github上面，然后通过devtools，我可以方便的把程序从github下载安装。

在github创建一个新的资源库：chinaWeather

https://github.com/bsspirit/chinaWeather

提交本地代码到github

~ cd /home/conan/R/chinaWeather
~ git init
~ git add .
~ git commit -m 'init commit'
~ git remote add origin https://github.com/bsspirit/chinaWeather
~ git push -u origin master

To https://github.com/bsspirit/chinaWeather
 * [new branch]      master -> master
Branch master set up to track remote branch master from origin.

通过devtools下载，并安装代码。
现在我的chinaWeather包，已经在github上面发布了，如果其他的同学想使用可以下面命令安装。

> library(devtools)
> install_github("chinaWeather","bsspirit")
Installing github repo(s) chinaWeather/master from bsspirit
Downloading chinaWeather.zip from https://github.com/bsspirit/chinaWeather/archive/master.zip
Installing package from /tmp/RtmpSaXYcA/chinaWeather.zip
Installing chinaWeather
'/usr/lib/R/bin/R' --vanilla CMD INSTALL  \
  '/tmp/RtmpSaXYcA/chinaWeather-master'  \
  --library='/home/conan/R/x86_64-pc-linux-gnu-library/3.0'  \
  --with-keep.source --install-tests

* installing *source* package 'chinaWeather' ...
** R
** inst
** preparing package for lazy loading
** help
*** installing help indices
** building package indices
** testing if installed package can be loaded
* DONE (chinaWeather)

#测试包
> library(chinaWeather)
> filename()
[1] "20130805.csv"

#查看文档
> ?filename
filename             package:chinaWeather              R Documentation
Define a filename from current date.
Description:
     Define a filename from current date.
Usage:
       filename(date = Sys.time())
Arguments:
    date: input a date type
Value:
     character a file name
Examples:
     filename()
     filename(as.Date("20110701",format="%Y%m%d"))

我们完成了，开发R包的全部流程。依赖于devtools, roxygen2, testthat三个包，真是事半功倍，比起完全手动操作提高效率了很多！！

希望更多的朋友，可以站在巨人的肩膀前行，创造让人惊叹的成果来！

http://blog.fens.me/