This is the sequel of this post where we look at ways to build javadoc documentation as part of an R package

Ant has the javadoc task which we will use to build html files from java sources, leading to this modified build script with the new javadoc target:

   1 <project name="Hello Java World" basedir="." default="build" >
   2 
   3   <property name="target.dir" value="../inst/java" />
   4   <property name="javadoc.dir" value="../inst/javadoc" />
   5   
   6   <target name="clean">
   7     <delete dir="bin" />
   8     <delete dir="${javadoc.dir}" />
   9   </target>
  10   
  11   <target name="compile">
  12     <mkdir dir="bin"/>
  13     <javac srcdir="src" destdir="bin" />
  14   </target>
  15   
  16   <target name="javadoc">
  17     <mkdir dir="${javadoc.dir}" />
  18     <javadoc access="public" destdir="${javadoc.dir}"
  19       author="true" version="true" use="true" 
  20       windowtitle="helloJavaWorld - Java API">
  21         
  22        <fileset dir="src" defaultexcludes="yes">
  23             <include name="**/*.java"/>
  24         </fileset>
  25           
  26     </javadoc>
  27   </target>
  28   
  29   <target name="build" depends="compile,javadoc">
  30     <jar jarfile="${target.dir}/hellojavaworld.jar">
  31       <fileset dir="bin" />
  32     </jar>
  33   </target>
  34   
  35 </project>
  36 

so that when we run "R CMD build", the directory inst/javadoc gets created and filled with documentation generated from the java sources

The next thing we need is a way to access this documentation from R documentation, so we will just add a link to it from the Rd file, I have added this into the helloJavaWorld.Rd file in the seealso section:

18 \seealso{\link[helloJavaWorld:../javadoc/index]{The Java API of the package}}

This is not a perfect solution but gives a starting point. Potential issues, things to improve :

• It would be better to have a link in the 00Index.html file, but there currently is no way to do something like that
• A way to jump back to the R documentation from the java documentation is needed

I have posted a copy of the built package here, and you can download the source of this version here

Next step, use the junitreport ant task to make a report of unit tests of the java code