{"id":140,"date":"2026-10-12T12:31:49","date_gmt":"2026-10-12T12:31:49","guid":{"rendered":"http:\/\/www.scmgalaxy.com\/tutorials\/2009\/06\/20\/ant-script-to-reset-buildnumber\/"},"modified":"2026-10-12T12:31:49","modified_gmt":"2026-10-12T12:31:49","slug":"ant-script-to-reset-buildnumber","status":"publish","type":"post","link":"https:\/\/www.devopsschool.com\/blog\/ant-script-to-reset-buildnumber\/","title":{"rendered":"Apache Ant Script to Reset and Increment Build Numbers (CI-Friendly Modes)"},"content":{"rendered":"\n

Originally published on 2009-06-20; fully revised and updated.<\/em><\/p>\n\n\n\n

This guide shows how to manage a resettable, multi-part build number in Apache Ant. It is useful for teams maintaining Ant-based CI\/release pipelines and needing predictable version increments for major, minor, hotfix, revision, and optional continuous builds.<\/p>\n\n\n\n

Source context: original DevOpsSchool post<\/a>.<\/p>\n\n\n\n

\"Ant<\/figure>\n\n\n\n

How this build numbering pattern works<\/h2>\n\n\n\n

The script keeps version state in a build.number<\/code> file and updates it based on -Dincrement=...<\/code>. By default, the build number is four parts (major.minor.hotfix.revision<\/code>). For continuous builds, it can include a fifth part (continuous<\/code>).<\/p>\n\n\n\n

increment value<\/th>What changes<\/th>Output format<\/th>Example command<\/th><\/tr><\/thead>
(not set)<\/td>Revision increments by 1<\/td>major.minor.hotfix.revision<\/td>ant<\/td><\/tr>
major<\/td>major +1, minor=1, hotfix=0, revision=1<\/td>major.minor.hotfix.revision<\/td>ant -Dincrement=major<\/td><\/tr>
minor<\/td>minor +1, hotfix=0, revision=1<\/td>major.minor.hotfix.revision<\/td>ant -Dincrement=minor<\/td><\/tr>
hotfix<\/td>hotfix +1, revision=1<\/td>major.minor.hotfix.revision<\/td>ant -Dincrement=hotfix<\/td><\/tr>
continuous<\/td>continuous +1<\/td>major.minor.hotfix.revision.continuous<\/td>ant -Dincrement=continuous<\/td><\/tr>
contReset<\/td>continuous=1<\/td>major.minor.hotfix.revision.continuous<\/td>ant -Dincrement=contReset<\/td><\/tr>
rebuild<\/td>No counter change in the provided switch case<\/td>major.minor.hotfix.revision<\/td>ant -Dincrement=rebuild<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Create the build.number state file<\/h2>\n\n\n\n

Initialize the property file once in your project root:<\/p>\n\n\n

major.number=1\nminor.number=0\nhotfix.number=0\nrevision.number=0\ncontinuous.number=0<\/code><\/span><\/pre>\n\n\n
Add task definitions and targets in build.xml<\/h2>\n\n\n\n
The original snippet relies on Ant-Contrib tasks (such as var<\/code>, switch<\/code>, math<\/code>, if<\/code>) plus an unset<\/code> task from Antelope.<\/p>\n\n\n\n
Task definitions<\/h3>\n\n\n
<taskdef<\/span> resource<\/span>=\"net\/sf\/antcontrib\/antlib.xml\"<\/span>\/><\/span>\n<taskdef<\/span> name<\/span>=\"unset\"<\/span> classname<\/span>=\"ise.antelope.tasks.Unset\"<\/span>\/><\/span><\/code><\/span>Code language:<\/span> HTML, XML<\/span> (<\/span>xml<\/span>)<\/span><\/small><\/pre>\n\n\n
Target 1: initialize counters from build.number<\/h3>\n\n\n
<target<\/span> name<\/span>=\"initBuildNum\"<\/span> description<\/span>=\"Get current build number properties\"<\/span>><\/span>\n    <property<\/span> file<\/span>=\"build.number\"<\/span>\/><\/span>\n    <var<\/span> name<\/span>=\"next.major\"<\/span> value<\/span>=\"${major.number}\"<\/span>\/><\/span>\n    <var<\/span> name<\/span>=\"next.minor\"<\/span> value<\/span>=\"${minor.number}\"<\/span>\/><\/span>\n    <var<\/span> name<\/span>=\"next.hotfix\"<\/span> value<\/span>=\"${hotfix.number}\"<\/span>\/><\/span>\n    <var<\/span> name<\/span>=\"next.revision\"<\/span> value<\/span>=\"${revision.number}\"<\/span>\/><\/span>\n    <var<\/span> name<\/span>=\"next.continuous\"<\/span> value<\/span>=\"${continuous.number}\"<\/span>\/><\/span>\n<\/target<\/span>><\/span><\/code><\/span>Code language:<\/span> HTML, XML<\/span> (<\/span>xml<\/span>)<\/span><\/small><\/pre>\n\n\n
Target 2: apply increment logic<\/h3>\n\n\n
<target<\/span> name<\/span>=\"getBuildNum\"<\/span>><\/span>\n    <switch<\/span> value<\/span>=\"${increment}\"<\/span>><\/span>\n        <case<\/span> value<\/span>=\"rebuild\"<\/span>\/><\/span>\n\n        <case<\/span> value<\/span>=\"major\"<\/span>><\/span>\n            <math<\/span> result<\/span>=\"next.major\"<\/span> operand1<\/span>=\"${next.major}\"<\/span> operation<\/span>=\"+\"<\/span> operand2<\/span>=\"1\"<\/span> datatype<\/span>=\"int\"<\/span>\/><\/span>\n            <var<\/span> name<\/span>=\"next.minor\"<\/span> value<\/span>=\"1\"<\/span>\/><\/span>\n            <var<\/span> name<\/span>=\"next.hotfix\"<\/span> value<\/span>=\"0\"<\/span>\/><\/span>\n            <var<\/span> name<\/span>=\"next.revision\"<\/span> value<\/span>=\"1\"<\/span>\/><\/span>\n        <\/case<\/span>><\/span>\n\n        <case<\/span> value<\/span>=\"minor\"<\/span>><\/span>\n            <math<\/span> result<\/span>=\"next.minor\"<\/span> operand1<\/span>=\"${next.minor}\"<\/span> operation<\/span>=\"+\"<\/span> operand2<\/span>=\"1\"<\/span> datatype<\/span>=\"int\"<\/span>\/><\/span>\n            <var<\/span> name<\/span>=\"next.hotfix\"<\/span> value<\/span>=\"0\"<\/span>\/><\/span>\n            <var<\/span> name<\/span>=\"next.revision\"<\/span> value<\/span>=\"1\"<\/span>\/><\/span>\n        <\/case<\/span>><\/span>\n\n        <case<\/span> value<\/span>=\"hotfix\"<\/span>><\/span>\n            <math<\/span> result<\/span>=\"next.hotfix\"<\/span> operand1<\/span>=\"${next.hotfix}\"<\/span> operation<\/span>=\"+\"<\/span> operand2<\/span>=\"1\"<\/span> datatype<\/span>=\"int\"<\/span>\/><\/span>\n            <var<\/span> name<\/span>=\"next.revision\"<\/span> value<\/span>=\"1\"<\/span>\/><\/span>\n        <\/case<\/span>><\/span>\n\n        <case<\/span> value<\/span>=\"continuous\"<\/span>><\/span>\n            <math<\/span> result<\/span>=\"next.continuous\"<\/span> operand1<\/span>=\"${next.continuous}\"<\/span> operation<\/span>=\"+\"<\/span> operand2<\/span>=\"1\"<\/span> datatype<\/span>=\"int\"<\/span>\/><\/span>\n        <\/case<\/span>><\/span>\n\n        <case<\/span> value<\/span>=\"contReset\"<\/span>><\/span>\n            <var<\/span> name<\/span>=\"next.continuous\"<\/span> value<\/span>=\"1\"<\/span>\/><\/span>\n        <\/case<\/span>><\/span>\n\n        <default<\/span>><\/span>\n            <math<\/span> result<\/span>=\"next.revision\"<\/span> operand1<\/span>=\"${next.revision}\"<\/span> operation<\/span>=\"+\"<\/span> operand2<\/span>=\"1\"<\/span> datatype<\/span>=\"int\"<\/span>\/><\/span>\n        <\/default<\/span>><\/span>\n    <\/switch<\/span>><\/span>\n<\/target<\/span>><\/span><\/code><\/span>Code language:<\/span> HTML, XML<\/span> (<\/span>xml<\/span>)<\/span><\/small><\/pre>\n\n\n
Target 3: persist and expose full.buildnumber<\/h3>\n\n\n
<target<\/span> name<\/span>=\"setBuildNumber\"<\/span> depends<\/span>=\"initBuildNum,getBuildNum\"<\/span>><\/span>\n    <propertyfile<\/span> file<\/span>=\"build.number\"<\/span>><\/span>\n        <entry<\/span> key<\/span>=\"major.number\"<\/span> value<\/span>=\"${next.major}\"<\/span>\/><\/span>\n        <entry<\/span> key<\/span>=\"minor.number\"<\/span> value<\/span>=\"${next.minor}\"<\/span>\/><\/span>\n        <entry<\/span> key<\/span>=\"hotfix.number\"<\/span> value<\/span>=\"${next.hotfix}\"<\/span>\/><\/span>\n        <entry<\/span> key<\/span>=\"revision.number\"<\/span> value<\/span>=\"${next.revision}\"<\/span>\/><\/span>\n        <entry<\/span> key<\/span>=\"continuous.number\"<\/span> value<\/span>=\"${next.continuous}\"<\/span>\/><\/span>\n    <\/propertyfile<\/span>><\/span>\n\n    <unset<\/span> name<\/span>=\"major.number\"<\/span>\/><\/span>\n    <unset<\/span> name<\/span>=\"minor.number\"<\/span>\/><\/span>\n    <unset<\/span> name<\/span>=\"hotfix.number\"<\/span>\/><\/span>\n    <unset<\/span> name<\/span>=\"revision.number\"<\/span>\/><\/span>\n    <unset<\/span> name<\/span>=\"continuous.number\"<\/span>\/><\/span>\n\n    <property<\/span> file<\/span>=\"build.number\"<\/span>\/><\/span>\n\n    <if<\/span>><\/span>\n        <or<\/span>><\/span>\n            <equals<\/span> arg1<\/span>=\"${increment}\"<\/span> arg2<\/span>=\"continuous\"<\/span>\/><\/span>\n            <equals<\/span> arg1<\/span>=\"${increment}\"<\/span> arg2<\/span>=\"contReset\"<\/span>\/><\/span>\n        <\/or<\/span>><\/span>\n        <then<\/span>><\/span>\n            <property<\/span> name<\/span>=\"full.buildnumber\"<\/span> value<\/span>=\"${major.number}.${minor.number}.${hotfix.number}.${revision.number}.${continuous.number}\"<\/span>\/><\/span>\n        <\/then<\/span>><\/span>\n        <else<\/span>><\/span>\n            <property<\/span> name<\/span>=\"full.buildnumber\"<\/span> value<\/span>=\"${major.number}.${minor.number}.${hotfix.number}.${revision.number}\"<\/span>\/><\/span>\n        <\/else<\/span>><\/span>\n    <\/if<\/span>><\/span>\n\n    <echo<\/span>><\/span>${full.buildnumber}<\/echo<\/span>><\/span>\n<\/target<\/span>><\/span><\/code><\/span>Code language:<\/span> HTML, XML<\/span> (<\/span>xml<\/span>)<\/span><\/small><\/pre>\n\n\n
Make your main build target depend on setBuildNumber<\/code> so the version is calculated before packaging.<\/p>\n\n\n
<target<\/span> name<\/span>=\"build\"<\/span> depends<\/span>=\"setBuildNumber,compile,test,package\"<\/span>\/><\/span><\/code><\/span>Code language:<\/span> HTML, XML<\/span> (<\/span>xml<\/span>)<\/span><\/small><\/pre>\n\n\n
Command examples<\/h2>\n\n\n
ant\nant -Dincrement=major\nant -Dincrement=minor\nant -Dincrement=hotfix\nant -Dincrement=continuous\nant -Dincrement=contReset<\/code><\/span><\/pre>\n\n\n
Build number update workflow<\/h2>\n\n\n\n
\nflowchart TD\n    A[Run ant with optional increment] --> B[Load build.number]\n    B --> C[Evaluate increment mode]\n    C --> D[Update counters in memory]\n    D --> E[Write counters to build.number]\n    E --> F[Reload properties]\n    F --> G[Set full.buildnumber]\n    G --> H[Echo version for downstream targets]\n<\/pre>\n\n\n\n
Common pitfalls and best practices<\/h2>\n\n\n\n
  • Keep build.number<\/code> under controlled write access; concurrent CI jobs can overwrite each other.<\/li>
  • Ensure required task libraries are on Ant’s classpath before running this script.<\/li>
  • Document when to use major<\/code>, minor<\/code>, and hotfix<\/code> to avoid accidental version jumps.<\/li>
  • Be explicit in CI: pass -Dincrement=...<\/code> rather than relying on defaults.<\/li>
  • If you need immutable build metadata, publish ${full.buildnumber}<\/code> as an artifact variable after each run.<\/li><\/ul>\n","protected":false},"excerpt":{"rendered":"
    Learn how to implement a persistent build numbering scheme in Ant using a build.number file and three targets. This revised guide explains major, minor, hotfix, revision, and continuous increment modes with runnable examples.<\/p>\n","protected":false},"author":1,"featured_media":4095,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_joinchat":[],"footnotes":""},"categories":[12],"tags":[209,3326,3045,3322,3321,3320,3328,1122,3113,938,3319,3323,3325,3327,278,213,3324],"class_list":["post-140","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-apache-ant","tag-ant","tag-ant-reset-build-number","tag-ant-script","tag-ant-script-to-reset-buildnumber","tag-build-number","tag-buildnumber","tag-change-buildnumber","tag-guide","tag-how-to","tag-reference","tag-reset","tag-reset-buildnumber","tag-reset-buildnumber-by-ant-script","tag-resetting-build-numbers","tag-script","tag-tutorial","tag-use-ant-script-to-reset-buildnumber"],"_links":{"self":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/140","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=140"}],"version-history":[{"count":3,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/140\/revisions"}],"predecessor-version":[{"id":78989,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/140\/revisions\/78989"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/media\/4095"}],"wp:attachment":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/media?parent=140"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/categories?post=140"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/tags?post=140"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}