checkstyle.xml

<?xml version="1.0"?>
<!DOCTYPE module PUBLIC
  "-//Puppy Crawl//DTD Check Configuration 1.3//EN"
  "http://checkstyle.sourceforge.net/dtds/configuration_1_3.dtd">

<module name="Checker">
  <property name="charset" value="UTF-8"/>
  <property name="severity" value="warning"/>

  <module name="SuppressWarningsFilter"/>

  <!-- Checks whether files end with a newline -->
  <module name="NewlineAtEndOfFile"/>

  <!-- Checks for whitespace -->
  <module name="FileTabCharacter"/>

  <module name="RegexpMultiline">
    <property name="format" value="^([^\n ]+ )*(class|interface|enum) [^{]*\{\n[^\n}]"/>
    <property name="message" value="Empty row after class/interface/enum definition is required"/>
    <property name="fileExtensions" value="java"/>
  </module>

  <module name="RegexpMultiline">
    <property name="format" value="[^\n{]\n\}\n"/>
    <property name="message" value="Empty row before end of class/interface/enum is required"/>
    <property name="fileExtensions" value="java"/>
  </module>

  <module name="TreeWalker">
    <module name="SuppressWarningsHolder"/>

    <!-- Checks for naming conventions -->
    <module name="ConstantName"/>
    <module name="LocalFinalVariableName"/>
    <module name="LocalVariableName"/>
    <module name="MemberName"/>
    <module name="MethodName"/>
    <module name="PackageName"/>
    <module name="ParameterName"/>
    <module name="StaticVariableName"/>
    <module name="TypeName"/>

    <!-- Checks for imports -->
    <module name="ImportOrder">
      <property name="option" value="bottom"/>
      <property name="sortStaticImportsAlphabetically" value="true"/>
    </module>
    <module name="AvoidStarImport"/>
    <module name="IllegalImport"/>
    <module name="RedundantImport"/>
    <module name="UnusedImports"/>

    <!-- Checks for whitespace -->
    <module name="AnnotationLocation">
      <property name="allowSamelineSingleParameterlessAnnotation" value="false"/>
    </module>
    <module name="Indentation">
      <property name="basicOffset" value="2"/>
      <property name="braceAdjustment" value="0"/>
      <property name="caseIndent" value="2"/>
      <property name="throwsIndent" value="4"/>
      <property name="arrayInitIndent" value="2"/>
      <property name="lineWrappingIndentation" value="4"/>
    </module>
    <module name="EmptyForIteratorPad"/>
    <module name="GenericWhitespace"/>
    <module name="MethodParamPad"/>
    <module name="NoWhitespaceAfter"/>
    <module name="NoWhitespaceBefore"/>
    <module name="OperatorWrap"/>
    <module name="ParenPad"/>
    <module name="TypecastParenPad"/>
    <module name="WhitespaceAfter"/>
    <module name="WhitespaceAround"/>
    <module name="EmptyLineSeparator">
      <property name="allowNoEmptyLineBetweenFields" value="true"/>
      <property name="allowMultipleEmptyLines" value="false"/>
    </module>

    <!-- Checks for modifiers -->
    <module name="ModifierOrder"/>
    <module name="RedundantModifier"/>

    <!-- Checks for this usage -->
    <module name="RequireThis">
      <property name="validateOnlyOverlapping" value="false"/>
    </module>

    <!-- Checks for blocks -->
    <module name="AvoidNestedBlocks"/>
    <module name="EmptyBlock">
      <property name="option" value="text"/>
    </module>
    <module name="LeftCurly"/>
    <module name="NeedBraces"/>
    <module name="RightCurly"/>

    <!-- Checks for common coding problems -->
    <module name="EmptyStatement"/>
    <module name="EqualsHashCode"/>
    <module name="IllegalInstantiation"/>
    <module name="InnerAssignment"/>
    <module name="MissingSwitchDefault"/>
    <module name="SimplifyBooleanExpression"/>

    <!-- Checks for class design -->
    <module name="FinalClass"/>
    <module name="FinalLocalVariable"/>
    <module name="HideUtilityClassConstructor"/>
    <module name="InterfaceIsType"/>
    <module name="VisibilityModifier">
      <property name="packageAllowed" value="true"/>
      <property name="protectedAllowed" value="true"/>
      <property name="allowPublicFinalFields" value="true"/>
      <property name="allowPublicImmutableFields" value="true"/>
    </module>

    <!-- Miscellaneous other checks -->
    <module name="ArrayTypeStyle"/>
    <!--<module name="TodoComment"/>-->
    <module name="UpperEll"/>
    <module name="CommentsIndentation"/>
  </module>
</module>