codestyle/pmd-ruleset.xml

<?xml version="1.0" encoding="UTF-8"?>
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<ruleset name="Apache Druid PMD ruleset"
    xmlns="http://pmd.sourceforge.net/ruleset/2.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://pmd.sourceforge.net/ruleset/2.0.0 https://pmd.sourceforge.io/ruleset_2_0_0.xsd">

  <description>
This ruleset defines the PMD rules for the Apache Druid project.
  </description>

  <rule ref="category/java/codestyle.xml/UnnecessaryImport" />
  <rule ref="category/java/codestyle.xml/TooManyStaticImports" />
  <rule ref="category/java/bestpractices.xml/UnusedFormalParameter" />
  <rule ref="category/java/bestpractices.xml/UnusedLocalVariable" />
  <rule ref="category/java/bestpractices.xml/MissingOverride" />
  <rule name="ConfusingMethodName"
        language="java"
        message="Methods in the same class must not differ only by capitalization"
        class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
    <description>
      Prevent case-only method-name differences, which are easy to confuse at call sites.
      Methods that override inherited APIs are excluded because their names cannot be changed.
    </description>
    <priority>2</priority>
    <properties>
      <property name="xpath">
        <value>
<![CDATA[
for $method in //MethodDeclaration[@Overridden = false()]
return $method[
  some $other in $method/preceding-sibling::MethodDeclaration[@Overridden = false()]
  satisfies lower-case($method/@Name) = lower-case($other/@Name)
            and $method/@Name != $other/@Name
]
]]>
        </value>
      </property>
    </properties>
  </rule>
</ruleset>