Documentation Index | PMD Source Code Analyzer

Welcome to the documentation site for PMD and CPD!

Table of Contents

💡 Overview

PMD is a static source code analyzer. It finds common programming flaws like unused variables, empty catch blocks, unnecessary object creation, and so forth. It’s mainly concerned with Java and Apex, but supports 16 other languages.

PMD features many built-in checks (in PMD lingo, rules), which are documented for each language in our Rule references. We also support an extensive API to write your own rules, which you can do either in Java or as a self-contained XPath query.

PMD is most useful when integrated into your build process. It can then be used as a quality gate, to enforce a coding standard for your codebase. Among other things, PMD can be run:

CPD, the copy-paste detector, is also distributed with PMD. You can also use it in a variety of ways, which are documented here.

💾 Download

The latest release of PMD can be downloaded from our Github releases page.

The Logo is available from the Logo Project Page.

📖 Documentation

The rest of this page exposes the contents of the documentation site thematically, which you can further scope down using the blue filter buttons. To navigate the site, you may also use the search bar in the top right, or the sidebar on the left.

✨ Contributors

This project follows the all-contributors specification. Contributions of any kind welcome!

See credits for the complete list.

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  <button class="btn btn-primary" data-group="getting_started">Getting Started</button>
  <button class="btn btn-primary" data-group="userdocs">User documentation</button>
  <button class="btn btn-primary" data-group="extending">Extending PMD</button>
  <button class="btn btn-primary" data-group="contributing">Contributing</button>

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        Getting started
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            These pages summarize the gist of PMD usage to get you started quickly.
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                    <li><a href="pmd_userdocs_installation.html">Installation and basic CLI usage</a></li>
                
                    <li><a href="pmd_userdocs_making_rulesets.html">Making rulesets</a></li>
                
                    <li><a href="pmd_userdocs_configuring_rules.html">Configuring rules</a></li>
                
                    <li><a href="pmd_userdocs_extending_writing_rules_intro.html">Introduction to writing PMD rules</a></li>
                
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        Rule references
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            Pick your language to find out about the rule it supports.
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                    <li><a href="pmd_userdocs_3rdpartyrulesets.html"></a></li>
                
                    <li><a href="pmd_rules_apex.html">Apex</a></li>
                
                    <li><a href="pmd_rules_html.html">HTML</a></li>
                
                    <li><a href="pmd_rules_java.html">Java</a></li>
                
                    <li><a href="pmd_rules_jsp.html">Java Server Pages</a></li>
                
                    <li><a href="pmd_rules_ecmascript.html">JavaScript</a></li>
                
                    <li><a href="pmd_rules_kotlin.html">Kotlin</a></li>
                
                    <li><a href="pmd_rules_pom.html">Maven POM</a></li>
                
                    <li><a href="pmd_rules_modelica.html">Modelica</a></li>
                
                    <li><a href="pmd_rules_plsql.html">PLSQL</a></li>
                
                    <li><a href="pmd_rules_visualforce.html">Salesforce Visualforce</a></li>
                
                    <li><a href="pmd_rules_scala.html">Scala</a></li>
                
                    <li><a href="pmd_rules_swift.html">Swift</a></li>
                
                    <li><a href="pmd_rules_velocity.html">Velocity Template Language (VTL)</a></li>
                
                    <li><a href="pmd_rules_xml.html">XML</a></li>
                
                    <li><a href="pmd_rules_xsl.html">XSL</a></li>
                
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        Writing rules
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            These pages document the process of writing and testing custom rules and metrics for PMD.
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                    <li><a href="pmd_userdocs_extending_writing_rules_intro.html">Introduction to writing PMD rules</a></li>
                
                    <li><a href="pmd_userdocs_extending_your_first_rule.html">Your first rule</a></li>
                
                    <li><a href="pmd_userdocs_extending_writing_xpath_rules.html">Writing XPath rules</a></li>
                
                    <li><a href="pmd_userdocs_extending_writing_java_rules.html">Writing a custom rule</a></li>
                
                    <li><a href="pmd_userdocs_extending_designer_reference.html">The rule designer</a></li>
                
                    <li><a href="pmd_userdocs_extending_defining_properties.html">Defining rule properties</a></li>
                
                    <li><a href="pmd_userdocs_extending_rule_guidelines.html">Rule guidelines</a></li>
                
                    <li><a href="pmd_userdocs_extending_testing.html">Testing your rules</a></li>
                
                    <li><a href="pmd_userdocs_extending_writing_pmd_rules.html">Writing a custom rule</a></li>
                
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        Usage and configuration
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            Learn how to build effective and versatile rulesets.
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                    <li><a href="pmd_userdocs_migrating_to_pmd7.html">Migration Guide for PMD 7</a></li>
                
                    <li><a href="pmd_userdocs_installation.html">Installation and basic CLI usage</a></li>
                
                    <li><a href="pmd_userdocs_making_rulesets.html">Making rulesets</a></li>
                
                    <li><a href="pmd_userdocs_configuring_rules.html">Configuring rules</a></li>
                
                    <li><a href="pmd_userdocs_best_practices.html">Best Practices</a></li>
                
                    <li><a href="pmd_userdocs_suppressing_warnings.html">Suppressing warnings</a></li>
                
                    <li><a href="pmd_userdocs_incremental_analysis.html">Incremental Analysis</a></li>
                
                    <li><a href="pmd_userdocs_cli_reference.html">PMD CLI reference</a></li>
                
                    <li><a href="pmd_userdocs_report_formats.html">Report formats for PMD</a></li>
                
                    <li><a href="pmd_userdocs_3rdpartyrulesets.html">3rd party rulesets</a></li>
                
                    <li><a href="pmd_userdocs_cpd.html">Finding duplicated code with CPD</a></li>
                
                    <li><a href="pmd_userdocs_cpd_report_formats.html">Report formats for CPD</a></li>
                
                    <li><a href="pmd_userdocs_extending_ast_dump.html">Creating XML dump of the AST</a></li>
                
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        Contributing
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            If you'd like to help us build PMD, these topics may interest you. See you around!
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                    <li><a href="pmd_devdocs_development.html">Developer Resources</a></li>
                
                    <li><a href="pmd_devdocs_building.html">Building PMD from source</a></li>
                
                    <li><a href="pmd_devdocs_writing_documentation.html">Writing documentation</a></li>
                
                    <li><a href="pmd_devdocs_roadmap.html">Roadmap</a></li>
                
                    <li><a href="pmd_devdocs_how_pmd_works.html">How PMD Works</a></li>
                
                    <li><a href="pmd_devdocs_pmdtester.html">Pmdtester</a></li>
                
                    <li><a href="pmd_devdocs_rule_deprecation_policy.html">Rule deprecation policy</a></li>
                
                    <li><a href="pmd_devdocs_logging.html">Logging</a></li>
                
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        Tools and integrations
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            These pages describe solutions that integrate PMD within your build process.
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                    <li><a href="pmd_userdocs_tools_maven.html">Maven PMD Plugin</a></li>
                
                    <li><a href="pmd_userdocs_tools_gradle.html">Gradle</a></li>
                
                    <li><a href="pmd_userdocs_tools_ant.html">Ant Task Usage</a></li>
                
                    <li><a href="pmd_userdocs_tools_java_api.html">PMD Java API</a></li>
                
                    <li><a href="pmd_userdocs_tools_bld.html">bld PMD Extension</a></li>
                
                    <li><a href="pmd_userdocs_tools_ci.html">Continuous Integrations plugins</a></li>
                
                    <li><a href="pmd_userdocs_tools.html">Tools / Integrations</a></li>
                
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        Major contributions
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                    <li><a href="pmd_devdocs_major_rule_guidelines.html">Guidelines for standard rules</a></li>
                
                    <li><a href="pmd_devdocs_major_adding_new_language_javacc.html">Adding PMD support for a new JavaCC grammar based language</a></li>
                
                    <li><a href="pmd_devdocs_major_adding_new_language_antlr.html">Adding PMD support for a new ANTLR grammar based language</a></li>
                
                    <li><a href="pmd_devdocs_major_adding_new_cpd_language.html">How to add a new CPD language</a></li>
                
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