{"id":275,"date":"2026-10-13T07:11:09","date_gmt":"2026-10-13T07:11:09","guid":{"rendered":"http:\/\/www.scmgalaxy.com\/tutorials\/2010\/07\/22\/sample-ant-clean-prepare-and-compile-tasks\/"},"modified":"2026-10-13T07:11:10","modified_gmt":"2026-10-13T07:11:10","slug":"sample-ant-clean-prepare-and-compile-tasks","status":"publish","type":"post","link":"https:\/\/www.devopsschool.com\/blog\/sample-ant-clean-prepare-and-compile-tasks\/","title":{"rendered":"Apache Ant clean, prepare, and compile Targets: A Practical build.xml Walkthrough"},"content":{"rendered":"\n

Apache Ant organizes Java build automation into named targets with dependency chains. This guide is for engineers maintaining legacy or lightweight Java build systems, and it shows exactly how a clean \u2192 prepare \u2192 compile<\/strong> flow works, how to run it, and what to watch for in real projects.<\/p>\n\n\n\n

Originally published on 2010-07-22; fully revised and updated.<\/em><\/p>\n\n\n\n

\"Sample<\/figure>\n\n\n\n

What the clean, prepare, and compile targets do<\/h2>\n\n\n\n

This pattern separates build responsibilities into predictable stages:<\/p>\n\n\n\n

  • clean<\/strong>: removes previously generated output.<\/li>
  • prepare<\/strong>: recreates required directory structure.<\/li>
  • compile<\/strong>: compiles application and test sources using a shared classpath.<\/li><\/ul>\n\n\n\n

    Because Ant supports target dependencies<\/strong>, running compile<\/code> automatically triggers prepare<\/code>, which in turn triggers clean<\/code>.<\/p>\n\n\n\n

    Build dependency workflow<\/h2>\n\n\n\n

    The dependency chain below reflects the original logic and execution order.<\/p>\n\n\n\n

    \nflowchart TD\n    A[Run ant compile] --> B[clean target]\n    B --> C[Delete output and temp directories]\n    C --> D[prepare target]\n    D --> E[Create build directories]\n    E --> F[compile target]\n    F --> G[Compile src.dir sources]\n    G --> H[Compile src.tests.dir subset]\n    H --> I[Classes ready in temp.dir.classes]\n<\/pre>\n\n\n\n
    Complete build.xml example<\/h2>\n\n\n\n
    The original post showed core targets only. The example below keeps that logic and adds the minimal surrounding properties and classpath so it can be used as a practical template.<\/p>\n\n\n
    <project<\/span> name<\/span>=\"sample-build\"<\/span> default<\/span>=\"compile\"<\/span> basedir<\/span>=\".\"<\/span>><\/span>\n    <property<\/span> name<\/span>=\"src.dir\"<\/span> value<\/span>=\"src\"<\/span> \/><\/span>\n    <property<\/span> name<\/span>=\"src.tests.dir\"<\/span> value<\/span>=\"src-tests\"<\/span> \/><\/span>\n\n    <property<\/span> name<\/span>=\"dest.dir\"<\/span> value<\/span>=\"build\/dist\"<\/span> \/><\/span>\n    <property<\/span> name<\/span>=\"temp.dir\"<\/span> value<\/span>=\"build\/tmp\"<\/span> \/><\/span>\n    <property<\/span> name<\/span>=\"temp.dir.lib\"<\/span> value<\/span>=\"${temp.dir}\/lib\"<\/span> \/><\/span>\n    <property<\/span> name<\/span>=\"temp.dir.meta-inf\"<\/span> value<\/span>=\"${temp.dir}\/META-INF\"<\/span> \/><\/span>\n    <property<\/span> name<\/span>=\"temp.dir.web-inf\"<\/span> value<\/span>=\"${temp.dir}\/WEB-INF\"<\/span> \/><\/span>\n    <property<\/span> name<\/span>=\"temp.dir.classes\"<\/span> value<\/span>=\"${temp.dir}\/classes\"<\/span> \/><\/span>\n\n    <property<\/span> name<\/span>=\"lib.dir\"<\/span> value<\/span>=\"lib\"<\/span> \/><\/span>\n\n    <path<\/span> id<\/span>=\"build.class.path\"<\/span>><\/span>\n        <fileset<\/span> dir<\/span>=\"${lib.dir}\"<\/span> includes<\/span>=\"**\/*.jar\"<\/span> \/><\/span>\n    <\/path<\/span>><\/span>\n\n    <target<\/span> name<\/span>=\"clean\"<\/span>><\/span>\n        <echo<\/span>><\/span>=== CLEAN ===<\/echo<\/span>><\/span>\n        <delete<\/span> failonerror<\/span>=\"false\"<\/span>><\/span>\n            <fileset<\/span> dir<\/span>=\"${dest.dir}\"<\/span> includes<\/span>=\"**\/*\"<\/span> \/><\/span>\n        <\/delete<\/span>><\/span>\n        <delete<\/span> dir<\/span>=\"${temp.dir}\"<\/span> \/><\/span>\n    <\/target<\/span>><\/span>\n\n    <target<\/span> name<\/span>=\"prepare\"<\/span> depends<\/span>=\"clean\"<\/span>><\/span>\n        <echo<\/span>><\/span>=== PREPARE ===<\/echo<\/span>><\/span>\n        <mkdir<\/span> dir<\/span>=\"${dest.dir}\"<\/span> \/><\/span>\n        <mkdir<\/span> dir<\/span>=\"${temp.dir}\"<\/span> \/><\/span>\n        <mkdir<\/span> dir<\/span>=\"${temp.dir.lib}\"<\/span> \/><\/span>\n        <mkdir<\/span> dir<\/span>=\"${temp.dir.meta-inf}\"<\/span> \/><\/span>\n        <mkdir<\/span> dir<\/span>=\"${temp.dir.web-inf}\"<\/span> \/><\/span>\n        <mkdir<\/span> dir<\/span>=\"${temp.dir.classes}\"<\/span> \/><\/span>\n    <\/target<\/span>><\/span>\n\n    <target<\/span> name<\/span>=\"compile\"<\/span> depends<\/span>=\"prepare\"<\/span>><\/span>\n        <echo<\/span>><\/span>=== COMPILE ===<\/echo<\/span>><\/span>\n\n        <echo<\/span>><\/span>Compiling ${src.dir} files ...<\/echo<\/span>><\/span>\n        <javac<\/span> debug<\/span>=\"on\"<\/span> srcdir<\/span>=\"${src.dir}\"<\/span> destdir<\/span>=\"${temp.dir.classes}\"<\/span> includes<\/span>=\"**\/*.java\"<\/span>><\/span>\n            <classpath<\/span> refid<\/span>=\"build.class.path\"<\/span> \/><\/span>\n        <\/javac<\/span>><\/span>\n\n        <!-- Compile selected test sources --><\/span>\n        <echo<\/span>><\/span>Compiling ${src.tests.dir} files ...<\/echo<\/span>><\/span>\n        <javac<\/span> debug<\/span>=\"on\"<\/span> srcdir<\/span>=\"${src.tests.dir}\"<\/span> destdir<\/span>=\"${temp.dir.classes}\"<\/span> includes<\/span>=\"com\/**\/*.java\"<\/span>><\/span>\n            <classpath<\/span> refid<\/span>=\"build.class.path\"<\/span> \/><\/span>\n        <\/javac<\/span>><\/span>\n    <\/target<\/span>><\/span>\n<\/project<\/span>><\/span><\/code><\/span>Code language:<\/span> HTML, XML<\/span> (<\/span>xml<\/span>)<\/span><\/small><\/pre>\n\n\n
    Target comparison<\/h2>\n\n\n\n
    Target<\/th>Depends on<\/th>Main purpose<\/th>Key operations<\/th><\/tr><\/thead>
    clean<\/td>None<\/td>Remove prior build output<\/td>Delete ${dest.dir}<\/code> contents and ${temp.dir}<\/code><\/td><\/tr>
    prepare<\/td>clean<\/td>Create a known directory layout<\/td>Create destination, temp, classes, and metadata folders<\/td><\/tr>
    compile<\/td>prepare<\/td>Compile source code<\/td>Run javac<\/code> for main and selected test sources using build.class.path<\/code><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
    How to run these targets<\/h2>\n\n\n\n
    From the directory containing build.xml<\/code>:<\/p>\n\n\n
    ant clean\nant prepare\nant compile<\/code><\/span><\/pre>\n\n\n
    In day-to-day use, ant compile<\/code> is usually enough because dependencies execute upstream targets automatically.<\/p>\n\n\n\n
    Best practices<\/h2>\n\n\n\n
    • Keep target responsibilities narrow: cleanup, setup, and compilation should stay separate.<\/li>
    • Prefer explicit include patterns like **\/*.java<\/code> for predictable compilation scope.<\/li>
    • Define all referenced properties and path IDs in one place near the top of build.xml<\/code>.<\/li>
    • Be intentional about test output location; compiling tests into the same classes directory can blur boundaries.<\/li>
    • Use dependency chains instead of repeated commands so the build remains deterministic.<\/li><\/ul>\n","protected":false},"excerpt":{"rendered":"
      Learn how to structure a simple Ant build pipeline using clean, prepare, and compile targets with explicit dependencies. This revision includes a complete build.xml example, execution commands, and a workflow diagram.<\/p>\n","protected":false},"author":1,"featured_media":4415,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_joinchat":[],"footnotes":""},"categories":[12],"tags":[4227,3827,4226,4220,683,91,4221,3420,4225,519,1122,4222,938,4218,4224,4228,4223],"class_list":["post-275","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-apache-ant","tag-and-compile-example","tag-ant-build","tag-ant-clean","tag-ant-example","tag-apache-ant","tag-build","tag-clean","tag-compile","tag-echo","tag-example","tag-guide","tag-prepare","tag-reference","tag-sample","tag-scipt","tag-simple-ant-example","tag-task"],"_links":{"self":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/275","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/comments?post=275"}],"version-history":[{"count":3,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/275\/revisions"}],"predecessor-version":[{"id":79104,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/275\/revisions\/79104"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/media\/4415"}],"wp:attachment":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/media?parent=275"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/categories?post=275"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/tags?post=275"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}