How to develope a method to substitute repetitive code block - ant

Question

I am new in ant, so I wasn't able to find an approach to make my buld file a bit more elegant. I believe there is an approach to substitute repetitive block of code into my build. So here is build file:
<project basedir="../../../" name="do-report" default="zip-all">
<xmlproperty keeproot="false" file="implementation/xml/ant/properties.xml"/>
<!-- -->
<taskdef resource="net/sf/antcontrib/antcontrib.properties">
<classpath>
<pathelement location="${infrastructure-base-dir}/apache-ant-1.9.6/lib/ant-contrib-0.3.jar"/>
</classpath>
</taskdef>
<!-- -->
<target name="clean">
<delete dir="${dita-odt.path.odt-unzipped-base-dir}" includeemptydirs="true" failonerror="no"/>
<delete dir="examples/intermediate/odt-files" includeemptydirs="true" failonerror="no"/>
</target>
<!-- -->
<target name="unzip-writing-odt-file" depends="clean">
<unzip src="${dita-odt.path.writing-odt}" dest="${dita-odt.path.writing-odt-unzipped}"/>
</target>
<!-- -->
<target name="extract-common-paths" depends="unzip-writing-odt-file">
<foreach target="copy-text-path" param="file">
<path>
<fileset dir="${dita-odt.path.text-xml-base-dir}">
<include name="**/content.xml"/>
</fileset>
</path>
</foreach>
</target>
<!-- -->
<target name="copy-text-path" description="copy text-xml path relative to text-xml-base-dir">
<dirname property="text-absolute-dir-path" file="${file}"/>
<property name="absolute-path-text-base-dir" location="${dita-odt.path.text-xml-base-dir}"/>
<pathconvert property="common-path" dirsep="/">
<path location="${text-absolute-dir-path}"/>
<map from="${absolute-path-text-base-dir}/" to=""/>
</pathconvert>
<antcall target="copy-writing-unzipped">
<param name="common-path" value="${common-path}"/>
</antcall>
</target>
<!-- -->
<target name="copy-writing-unzipped">
<echo>${common-path}</echo>
<copy todir="${dita-odt.path.odt-unzipped-base-dir}/${common-path}">
<fileset dir="${dita-odt.path.writing-odt-unzipped}">
<include name="**/*"/>
</fileset>
</copy>
</target>
<!-- -->
<target name="transform-all" depends="extract-common-paths">
<foreach target="transform" param="file">
<path>
<fileset dir="${dita-odt.path.text-xml-base-dir}">
<include name="**/content.xml"/>
</fileset>
</path>
</foreach>
</target>
<!-- -->
<target name="transform">
<basename property="file-base-name" file="${file}"/>
<dirname property="file-dir-absolute-path" file="${file}"/>
<property name="text-xml-base-dir-absolute-path" location="${dita-odt.path.text-xml-base-dir}"/>
<pathconvert property="common-path" dirsep="/">
<path location="${file-dir-absolute-path}"/>
<map from="${text-xml-base-dir-absolute-path}/" to=""/>
</pathconvert>
<!--Substitutes backslashes with forword slashes. Basedir is a reserved property that returns absolute path with separator symbols of the current OS.-->
<pathconvert dirsep="/" property="base-dir-unix">
<path location="${basedir}"/>
</pathconvert>
<echo>TRANSFORM TO: ${dita-odt.path.odt-unzipped-base-dir}/${common-path}/${file-base-name}</echo>
<xslt in="${file}" out="${dita-odt.path.odt-unzipped-base-dir}/${common-path}/${file-base-name}" style="${dita-odt.path.text-odt-xsl}" extension=".xml" force="true">
<param name="dir-path-styles-xml" expression="${dita-odt.path.odt-unzipped-base-dir}/${common-path}"/>
<param name="project-base-dir-absolute-path" expression="${base-dir-unix}"/>
<classpath location="${infrastructure-base-dir}/${dita-odt.text-odt-xsl.processor}"/>
</xslt>
</target>
<!-- -->
<target name="zip-all" depends="transform-all" description="Turns all unzipped text folders into ODT files">
<foreach target="zip-odt" param="file">
<path>
<fileset dir="${dita-odt.path.odt-unzipped-base-dir}" includes="**/content.xml" excludes="writing/**"/>
</path>
</foreach>
</target>
<!-- -->
<target name="zip-odt">
<basename property="file-base-name" file="${file}"/>
<dirname property="file-dir-absolute-path" file="${file}"/>
<!--This property will be used to provided name for the produced ODT file. The document will have the same name as the folder that contains it.-->
<basename property="odt-doc-name" file="${file-dir-absolute-path}.odt"/>
<property name="odt-unzipped-base-dir-absolute-path" location="${dita-odt.path.odt-unzipped-base-dir}"/>
<pathconvert property="common-path" dirsep="/">
<path location="${file-dir-absolute-path}"/>
<map from="${odt-unzipped-base-dir-absolute-path}/" to=""/>
</pathconvert>
<echo>COMMON PATH: ${common-path}</echo>
<zip destfile="examples/intermediate/odt-files/${common-path}/${odt-doc-name}" basedir="${dita-odt.path.odt-unzipped-base-dir}/${common-path}" update="true"/>
</target>
<!-- -->
</project>
So this part of the script does pretty much the same, but shared among almost all the target in the project:
<dirname property="file-dir-absolute-path" file="${file}"/>
<property name="text-xml-base-dir-absolute-path" location="${dita-odt.path.text-xml-base-dir}"/>
<pathconvert property="common-path" dirsep="/">
<path location="${file-dir-absolute-path}"/>
<map from="${text-xml-base-dir-absolute-path}/" to=""/>
</pathconvert>
This part does nothing but to obtain part of a path. For example if ${file} stands for /folder/subfolder1/subfolder2 then take the path after /folder namely subfolder1/subfolder2 and assign it to a property. I this case that property is named common-path that holds same path for all the target. I examined MacroDef Task, but as far as I understand it doesn't return, only accepts some parameters in form of attributes. Anyway, any help would be much appreciated.

Answer 1

You are on the right track in considering <macrodef> to reduce repetitive code.
While it's true that <macrodef> doesn't return anything, <macrodef> can be given the name of a property to set. For example...
<macrodef name="my-hello">
<attribute name="person"/>
<attribute name="output-property"/>
<sequential>
<property name="#{output-property}" value="Hello, #{person}!"/>
</sequential>
</macrodef>
<my-hello person="Riko" output-property="say-hi-to-riko"/>
<echo>my-hello said: ${say-hi-to-riko}</echo>
...outputs...
[echo] my-hello said: Hello, Riko!
In this example, the caller of <my-hello> tells the macrodef to "return" its results in the say-hi-to-riko property.
Knowing this, several of the <target>s in your script can be converted to <macrodef>s that set properties...
<project name="ant-macrodef-pathconvert" default="extract-common-paths">
<taskdef resource="net/sf/antcontrib/antlib.xml" />
<property name="dita-odt.path.text-xml-base-dir" value="C:\temp\dita-odt"/>
<macrodef name="my-pathconvert">
<attribute name="file"/>
<attribute name="common-path-property"/>
<sequential>
<!-- <local> allows multiple calls to a macrodef. -->
<local name="file-dir-absolute-path"/>
<echo>In my-pathconvert for #{file}</echo>
<dirname property="file-dir-absolute-path" file="#{file}"/>
<property name="text-xml-base-dir-absolute-path"
location="${dita-odt.path.text-xml-base-dir}"/>
<pathconvert property="#{common-path-property}" dirsep="/">
<path location="${file-dir-absolute-path}"/>
<map from="${file-dir-absolute-path}/" to=""/>
</pathconvert>
</sequential>
</macrodef>
<macrodef name="copy-text-path"
description="copy text-xml path relative to text-xml-base-dir">
<attribute name="file"/>
<sequential>
<local name="common-path"/>
<echo>In copy-text-path for #{file}</echo>
<my-pathconvert file="#{file}" common-path-property="common-path"/>
<copy-writing-unzipped common-path="${common-path}"/>
</sequential>
</macrodef>
<macrodef name="copy-writing-unzipped">
<attribute name="common-path"/>
<sequential>
<echo>In copy-writing-unzipped for #{common-path}</echo>
<echo>copy task goes here.</echo>
</sequential>
</macrodef>
<target name="extract-common-paths">
<for param="file">
<path>
<fileset dir="${dita-odt.path.text-xml-base-dir}">
<include name="**/content.xml"/>
</fileset>
</path>
<sequential>
<copy-text-path file="#{file}"/>
</sequential>
</for>
</target>
</project>
In general, it's better to prefer calling <macrodef>s over calling <target>s directly. In the above example, <foreach> is replaced with <for> because <for> lets us call <macrodef>s.
Output
[echo] In copy-text-path for C:\temp\dita-odt\dir1\content.xml
[echo] In my-pathconvert for C:\temp\dita-odt\dir1\content.xml
[echo] In copy-writing-unzipped for C:/temp/dita-odt/dir1
[echo] copy task goes here.
[echo] In copy-text-path for C:\temp\dita-odt\dir2\content.xml
[echo] In my-pathconvert for C:\temp\dita-odt\dir2\content.xml
[echo] In copy-writing-unzipped for C:/temp/dita-odt/dir2
[echo] copy task goes here.