checkstyle.xml

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

<!--
  Checkstyle configuration that checks the sun coding conventions from:
    - the Java Language Specification at
      http://java.sun.com/docs/books/jls/second_edition/html/index.html
    - the Sun Code Conventions at http://java.sun.com/docs/codeconv/
    - the Javadoc guidelines at
      http://java.sun.com/j2se/javadoc/writingdoccomments/index.html
    - the JDK Api documentation http://java.sun.com/j2se/docs/api/index.html
    - some best practices
  Checkstyle is very configurable. Be sure to read the documentation at
  http://checkstyle.sf.net (or in your downloaded distribution).
  Most Checks are configurable, be sure to consult the documentation.
  To completely disable a check, just comment it out or delete it from the file.
  Finally, it is worth reading the documentation.
-->

<module name="Checker">
    <!--
        If you set the basedir property below, then all reported file
        names will be relative to the specified directory. See
        http://checkstyle.sourceforge.net/5.x/config.html#Checker
        <property name="basedir" value="${basedir}"/>
    -->

    <!-- Checks whether files end with a new line.                        -->
    <!-- See http://checkstyle.sf.net/config_misc.html#NewlineAtEndOfFile -->
    <module name="NewlineAtEndOfFile"/>

    <!-- Checks that property files contain the same keys.         -->
    <!-- See http://checkstyle.sf.net/config_misc.html#Translation -->
    <module name="Translation"/>

    <!-- Checks for Size Violations.                    -->
    <!-- See http://checkstyle.sf.net/config_sizes.html -->
    <module name="FileLength" />

    <!-- Checks for whitespace                               -->
    <!-- See http://checkstyle.sf.net/config_whitespace.html -->
    <module name="FileTabCharacter"/>

    <module name="LineLength">
        <property name="max" value="120"/>
    </module>

    <!-- Miscellaneous other checks.                   -->
    <!-- See http://checkstyle.sf.net/config_misc.html -->
    <module name="RegexpSingleline">
       <property name="format" value="\s+$"/>
       <property name="minimum" value="0"/>
       <property name="maximum" value="0"/>
       <property name="message" value="Line has trailing spaces."/>
    </module>

    <module name="SuppressionFilter">
        <property name="file" value="checkstyle-suppressions.xml" />
    </module>

    <module name="TreeWalker">

        <!-- Checks for Javadoc comments.                     -->
        <!-- See http://checkstyle.sf.net/config_javadoc.html -->
        <!-- module name="JavadocMethod"/ -->
        <module name="JavadocType"/>
        <module name="JavadocStyle"/>


        <!-- Checks for Naming Conventions.                  -->
        <!-- See http://checkstyle.sf.net/config_naming.html -->
        <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 Headers                                -->
        <!-- See http://checkstyle.sf.net/config_header.html   -->
        <!-- <module name="Header">                            -->
            <!-- The follow property value demonstrates the ability     -->
            <!-- to have access to ANT properties. In this case it uses -->
            <!-- the ${basedir} property to allow Checkstyle to be run  -->
            <!-- from any directory within a project. See property      -->
            <!-- expansion,                                             -->
            <!-- http://checkstyle.sf.net/config.html#properties        -->
            <!-- <property                                              -->
            <!--     name="headerFile"                                  -->
            <!--     value="${basedir}/java.header"/>                   -->
        <!-- </module> -->

        <!-- Following interprets the header file as regular expressions. -->
        <!-- <module name="RegexpHeader"/>                                -->


        <!-- Checks for imports                              -->
        <!-- See http://checkstyle.sf.net/config_import.html -->
        <module name="AvoidStarImport"/>
        <module name="IllegalImport"/> <!-- defaults to sun.* packages -->
        <module name="RedundantImport"/>
        <module name="UnusedImports"/>
        <module name="ImportOrderCheck">
            <property name="groups" value="*,javax,java"/>
            <property name="ordered" value="true"/>
            <property name="separated" value="true"/>
            <property name="option" value="bottom"/>
            <property name="sortStaticImportsAlphabetically" value="true"/>
        </module>

        <!-- Checks for Size Violations.                    -->
        <!-- See http://checkstyle.sf.net/config_sizes.html -->
        <module name="MethodLength"/>
        <module name="ParameterNumber">
           <property name="max" value="20"/>
        </module>


        <!-- Checks for whitespace                               -->
        <!-- See http://checkstyle.sf.net/config_whitespace.html -->
        <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">
            <property name="allowEmptyConstructors" value="true"/>
            <property name="allowEmptyMethods" value="true"/>
            <property name="allowEmptyTypes" value="true"/>
        </module>


        <!-- Modifier Checks                                    -->
        <!-- See http://checkstyle.sf.net/config_modifiers.html -->
        <module name="ModifierOrder"/>
        <module name="RedundantModifier"/>


        <!-- Checks for blocks. You know, those {}'s         -->
        <!-- See http://checkstyle.sf.net/config_blocks.html -->
        <module name="AvoidNestedBlocks"/>
        <module name="EmptyBlock"/>
        <module name="LeftCurly"/>
        <module name="NeedBraces"/>
        <module name="RightCurly"/>


        <!-- Checks for common coding problems               -->
        <!-- See http://checkstyle.sf.net/config_coding.html -->
        <!-- module name="AvoidInlineConditionals"/ -->
        <!-- module name="DoubleCheckedLocking"/ -->    <!-- MY FAVOURITE -->
        <module name="EmptyStatement"/>
        <module name="EqualsHashCode"/>
        <module name="HiddenField">
            <property name="ignoreConstructorParameter" value="true"/>
            <property name="ignoreSetter" value="true"/>
        </module>
        <module name="IllegalInstantiation"/>
        <module name="InnerAssignment"/>
        <!-- module name="MagicNumber"/ -->
        <module name="MissingSwitchDefault"/>
        <!-- module name="RedundantThrows"/ -->
        <module name="SimplifyBooleanExpression"/>
        <module name="SimplifyBooleanReturn"/>

        <!-- Checks for class design                         -->
        <!-- See http://checkstyle.sf.net/config_design.html -->
        <module name="DesignForExtension"/>
        <module name="FinalClass"/>
        <module name="HideUtilityClassConstructor"/>
        <module name="InterfaceIsType"/>
        <!-- module name="VisibilityModifier"/ -->


        <!-- Miscellaneous other checks.                   -->
        <!-- See http://checkstyle.sf.net/config_misc.html -->
        <module name="ArrayTypeStyle"/>
        <!-- module name="FinalParameters"/ -->
        <module name="TodoComment"/>
        <module name="UpperEll"/>

        <!-- See http://checkstyle.sourceforge.net/config_misc.html#Indentation -->
        <module name="Indentation"/>
    </module>

</module>