allwpilib/styleguide/pmd-ruleset.xml

<?xml version="1.0"?>
<ruleset name="WPILibRuleset"
  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 http://pmd.sourceforge.net/ruleset_2_0_0.xsd">

  <description>PMD Ruleset for WPILib</description>

  <!-- Generated files -->
  <exclude-pattern>.*/*EntryImpl\.java</exclude-pattern>
  <exclude-pattern>.*/*Subscriber\.java</exclude-pattern>
  <exclude-pattern>.*/Timestamped.*\.java</exclude-pattern>
  <exclude-pattern>.*/units/measure/.*\.java</exclude-pattern>

  <exclude-pattern>.*/*IntegrationTests.*</exclude-pattern>
  <exclude-pattern>.*/*JNI.*</exclude-pattern>
  <exclude-pattern>.*/math/proto.*</exclude-pattern>
  <exclude-pattern>.*/command3/proto.*</exclude-pattern>

  <rule ref="category/java/bestpractices.xml">
    <exclude name="AccessorClassGeneration" />
    <exclude name="AccessorMethodGeneration" />
    <exclude name="AvoidPrintStackTrace" />
    <exclude name="AvoidReassigningCatchVariables" />
    <exclude name="AvoidReassigningParameters" />
    <exclude name="AvoidUsingHardCodedIP" />
    <exclude name="ConstantsInInterface" />
    <exclude name="ExhaustiveSwitchHasDefault" />
    <exclude name="LooseCoupling" />
    <exclude name="NonExhaustiveSwitch" />
    <exclude name="PreserveStackTrace" />
    <exclude name="ReplaceHashtableWithMap" />
    <exclude name="ReplaceVectorWithList" />
    <exclude name="SystemPrintln" />
    <exclude name="UnitTestAssertionsShouldIncludeMessage" />
    <exclude name="UnitTestContainsTooManyAsserts" />
    <exclude name="UnitTestShouldIncludeAssert" />
    <exclude name="UnitTestShouldUseAfterAnnotation" />
    <exclude name="UnitTestShouldUseBeforeAnnotation" />
    <exclude name="UnitTestShouldUseTestAnnotation" />
    <exclude name="UseVarargs" />
  </rule>
  <rule ref="category/java/bestpractices.xml/UnusedPrivateMethod">
    <properties>
      <property name="violationSuppressRegex"
        value=".*'.*Arguments\(\)'.*" />
    </properties>
  </rule>
  <rule ref="category/java/bestpractices.xml/UnusedLocalVariable">
    <properties>
      <property name="violationSuppressXPath" value="//Resource"/>
    </properties>
  </rule>

  <rule ref="category/java/design.xml">
    <exclude name="AvoidThrowingNewInstanceOfSameException" />
    <exclude name="AvoidThrowingRawExceptionTypes" />
    <exclude name="CognitiveComplexity" />
    <exclude name="CouplingBetweenObjects" />
    <exclude name="CyclomaticComplexity" />
    <exclude name="DataClass" />
    <exclude name="ExceptionAsFlowControl" />
    <exclude name="ExcessiveImports" />
    <exclude name="ExcessiveParameterList" />
    <exclude name="ExcessivePublicCount" />
    <exclude name="GodClass" />
    <exclude name="LawOfDemeter" />
    <exclude name="LoosePackageCoupling" />
    <exclude name="NPathComplexity" />
    <exclude name="NcssCount" />
    <exclude name="TooManyFields" />
    <exclude name="TooManyMethods" />
  </rule>

  <rule ref="category/java/errorprone.xml">
    <exclude name="AssignmentToNonFinalStatic" />
    <exclude name="AvoidCatchingThrowable" />
    <exclude name="AvoidDuplicateLiterals" />
    <exclude name="AvoidLiteralsInIfCondition" />
    <exclude name="CloseResource" />
    <exclude name="ConstructorCallsOverridableMethod" />
    <exclude name="DoNotTerminateVM" />
    <exclude name="EmptyCatchBlock" />
    <exclude name="FinalizeDoesNotCallSuperFinalize" />
    <exclude name="JUnitSpelling" />
    <exclude name="MissingSerialVersionUID" />
    <exclude name="NonSerializableClass" />
    <exclude name="NullAssignment" />
  </rule>

  <rule ref="category/java/multithreading.xml">
    <exclude name="AvoidSynchronizedAtMethodLevel" />
    <exclude name="AvoidSynchronizedStatement" />
    <exclude name="AvoidUsingVolatile" />
    <exclude name="DoNotUseThreads" />
    <exclude name="UseConcurrentHashMap" />
  </rule>

  <rule ref="category/java/performance.xml">
    <exclude name="AvoidInstantiatingObjectsInLoops" />
    <!--
      This rule is in place to save three (!) bytecode instructions when initializing a field to its default value.
      Code that's more readable due to having explicit initial values is more important than reducing class size by a
      few bytes.
    -->
    <exclude name="RedundantFieldInitializer" />
  </rule>

  <rule name="UnnecessaryCastRule" language="java"
    message="Avoid unnecessary casts"
    class="net.sourceforge.pmd.lang.java.rule.codestyle.UnnecessaryCastRule"
    externalInfoUrl="https://github.com/pmd/pmd/blob/master/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/rule/codestyle/UnnecessaryCastRule.java" />

  <!-- Custom Rules -->
  <rule name="UseRequireNonNull"
    message="Use Objects.requireNonNull() instead of throwing a NullPointerException yourself."
    language="java" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
    <description>Use Objects.requireNonNull() instead of throwing a
      NullPointerException yourself.</description>
    <properties>
      <property name="xpath">
        <value>
          <![CDATA[
            //IfStatement[child::Expression//NullLiteral]/Statement//ThrowStatement/Expression/PrimaryExpression/PrimaryPrefix/AllocationExpression/ClassOrInterfaceType[@Image='NullPointerException']
          ]]>
        </value>
      </property>
    </properties>
    <priority>3</priority>
    <example>
<![CDATA[
                public class Example {
                    public Example(Object example) {
                        if (example == null) {
                            throw new NullPointerException();
                        }
                    }
                }
            ]]>
    </example>
  </rule>
</ruleset>