pmd

PMD is an extensible cross-language static code analyzer that finds common programming flaws and code quality issues. It focuses on detecting potential bugs, inefficient code patterns, and maintainability issues rather than just style violations.

Key Features:

Multi-Language Support: Analyzes Java, JavaScript, Apex, Swift, Kotlin, and 16 other languages with 400+ built-in rules
Advanced Bug Detection: Identifies unused variables, empty catch blocks, unnecessary object creation, and potential null pointer exceptions
Code Quality Analysis: Detects complex code patterns, inefficient algorithms, and design principle violations
Copy-Paste Detection: Includes CPD (Copy-Paste Detector) to find duplicated code across multiple languages
AST-Based Analysis: Uses JavaCC and ANTLR parsers to analyze abstract syntax trees for deep code understanding
Custom Rule Support: Extensible with custom rules written in Java or XPath queries
Comprehensive Reporting: Supports multiple output formats including SARIF for modern toolchain integration

pmd documentation

Version in MegaLinter: 7.15.0
Visit Official Web Site
See How to configure pmd rules
- If custom java-pmd-ruleset.xml config file isn't found, java-pmd-ruleset.xml will be used
See How to disable pmd rules in files
See Index of problems detected by pmd

Configuration in MegaLinter

Enable pmd by adding JAVA_PMD in ENABLE_LINTERS variable
Disable pmd by adding JAVA_PMD in DISABLE_LINTERS variable

Variable	Description	Default value
JAVA_PMD_ARGUMENTS	User custom arguments to add in linter CLI call Ex: `-s --foo "bar"`
JAVA_PMD_COMMAND_REMOVE_ARGUMENTS	User custom arguments to remove from command line before calling the linter Ex: `-s --foo "bar"`
JAVA_PMD_FILTER_REGEX_INCLUDE	Custom regex including filter Ex: `(src\\|lib)`	Include every file
JAVA_PMD_FILTER_REGEX_EXCLUDE	Custom regex excluding filter Ex: `(test\\|examples)`	Exclude no file
JAVA_PMD_CLI_LINT_MODE	Override default CLI lint mode - `file`: Calls the linter for each file - `list_of_files`: Call the linter with the list of files as argument - `project`: Call the linter from the root of the project	`list_of_files`
JAVA_PMD_FILE_EXTENSIONS	Allowed file extensions. `"*"` matches any extension, `""` matches empty extension. Empty list excludes all files Ex: `[".py", ""]`	`[".java"]`
JAVA_PMD_FILE_NAMES_REGEX	File name regex filters. Regular expression list for filtering files by their base names using regex full match. Empty list includes all files Ex: `["Dockerfile(-.+)?", "Jenkinsfile"]`	Include every file
JAVA_PMD_PRE_COMMANDS	List of bash commands to run before the linter	None
JAVA_PMD_POST_COMMANDS	List of bash commands to run after the linter	None
JAVA_PMD_UNSECURED_ENV_VARIABLES	List of env variables explicitly not filtered before calling JAVA_PMD and its pre/post commands	None
JAVA_PMD_CONFIG_FILE	pmd configuration file nameUse `LINTER_DEFAULT` to let the linter find it	`java-pmd-ruleset.xml`
JAVA_PMD_RULES_PATH	Path where to find linter configuration file	Workspace folder, then MegaLinter default rules
JAVA_PMD_DISABLE_ERRORS	Run linter but consider errors as warnings	`false`
JAVA_PMD_DISABLE_ERRORS_IF_LESS_THAN	Maximum number of errors allowed	`0`
JAVA_PMD_CLI_EXECUTABLE	Override CLI executable	`['/usr/bin/pmd/bin/pmd']`

MegaLinter Flavors

This linter is available in the following flavors

Flavor	Description	Embedded linters
all	Default MegaLinter Flavor	126
cupcake	MegaLinter for the most commonly used languages	87
java	Optimized for JAVA based projects	54

Behind the scenes

How are identified applicable files

File extensions: .java

How the linting is performed

pmd is called once with the list of files as arguments (list_of_files CLI lint mode)

Example calls

pmd --rulesets java-pmd-ruleset.xml --dir myfile.java

pmd --rulesets java-pmd-ruleset.xml --file-list /tmp/list-off-files-generated-by-megalinter.txt

pmd --rulesets java-pmd-ruleset.xml --dir /path/to/sources

Help content

Usage: pmd [-hV] [COMMAND]
  -h, --help      Show this help message and exit.
  -V, --version   Print version information and exit.
Commands:
  check                The PMD standard source code analyzer
  cpd                  Copy/Paste Detector - find duplicate code
  designer             The PMD visual rule designer
  cpd-gui              GUI for the Copy/Paste Detector
                         Warning: May not support the full CPD feature set
  ast-dump             Dumps the AST of parsing source code
  generate-completion  Generate bash/zsh completion script for pmd.
Exit Codes:
  0   Successful analysis, no violations found
  1   An unexpected error occurred during execution
  2   Usage error, please refer to the command help
  4   Successful analysis, at least 1 violation found

Installation on mega-linter Docker image

Dockerfile commands :

# Parent descriptor install
ENV JAVA_HOME=/usr/lib/jvm/java-21-openjdk
ENV PATH="$JAVA_HOME/bin:${PATH}"
# Linter install
# renovate: datasource=github-tags depName=pmd/pmd extractVersion=^pmd_releases/(?<version>.*)$
ARG PMD_VERSION=7.15.0

RUN wget --quiet https://github.com/pmd/pmd/releases/download/pmd_releases%2F${PMD_VERSION}/pmd-dist-${PMD_VERSION}-bin.zip && \
    unzip pmd-dist-${PMD_VERSION}-bin.zip || echo "Error unzipping" && \
    rm pmd-dist-${PMD_VERSION}-bin.zip || echo "Error rm" && \
    mv pmd-bin-${PMD_VERSION} /usr/bin/pmd || echo "Error mv" && \
    chmod +x /usr/bin/pmd/bin/pmd || echo "Error chmod"