config/checkstyle/checkstyle.xml

<?xml version="1.0" encoding="UTF-8"?>
<!--
Licensed to the Apache Software Foundation (ASF) under one
or more contributor license agreements.  See the NOTICE file
distributed with this work for additional information
regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing,
software distributed under the License is distributed on an
"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, either express or implied.  See the License for the
specific language governing permissions and limitations
under the License.
-->

<!DOCTYPE module PUBLIC
          "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
          "https://checkstyle.org/dtds/configuration_1_3.dtd">
<!-- This configuration corresponds to the OFBiz coding conventions
     which are basically “Sun Coding Standards”
     + 150 characters line length
     + NewlineAtEndOfFile value="lf_cr_crlf" />
     -->
<module name="Checker">
    <module name="BeforeExecutionExclusionFileFilter">
        <property name="fileNamePattern" value="module\-info\.java$"/>
    </module>
    <property name="fileExtensions" value="java, properties, xml"/>

    <!-- General file conventions -->
    <module name="NewlineAtEndOfFile">
        <property name="lineSeparator" value="lf_cr_crlf" />
    </module>
    <module name="FileTabCharacter"/>
    <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="LineLength">
        <property name="max" value="150"/>
    </module>

    <module name="TreeWalker">
        <!-- 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="AvoidStarImport"/>
        <module name="IllegalImport"/>
        <module name="RedundantImport"/>
        <module name="UnusedImports">
            <property name="processJavadoc" value="false"/>
        </module>

        <!-- Checks for Size Violations -->
        <module name="MethodLength">
            <property name="tokens" value="METHOD_DEF"/>
            <property name="max" value="500"/>
            <property name="countEmpty" value="false"/>
        </module>
        <module name="ParameterNumber">
            <property name="max" value="10"/>
            <property name="tokens" value="METHOD_DEF"/>
            <property name="ignoreOverriddenMethods" value="true"/>
        </module>

        <!-- Checks for whitespace -->
        <module name="EmptyForIteratorPad"/>
        <module name="GenericWhitespace"/>
        <module name="MethodParamPad"/>
        <module name="NoWhitespaceAfter"/>
        <module name="NoWhitespaceBefore"/>
        <module name="OperatorWrap"/>
        <module name="SeparatorWrap">
            <property name="tokens"
                      value="COMMA,LPAREN,RPAREN,RBRACK,ARRAY_DECLARATOR"/>
            <property name="option" value="eol"/>
        </module>
        <module name="SeparatorWrap">
            <property name="tokens" value="DOT,METHOD_REF,ELLIPSIS,AT"/>
            <property name="option" value="nl"/>
        </module>
        <module name="ParenPad"/>
        <module name="TypecastParenPad"/>
        <module name="WhitespaceAfter"/>
        <module name="WhitespaceAround"/>
        <module name="SingleSpaceSeparator"/>

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

        <!-- Checks for blocks. You know, those {}'s -->
        <module name="AvoidNestedBlocks"/>
        <module name="EmptyBlock"/>
        <module name="LeftCurly"/>
        <module name="NeedBraces">
            <property name="allowSingleLineStatement" value="true"/>
        </module>
        <module name="RightCurly"/>

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

        <!-- Checks for class design -->
        <module name="DesignForExtension">
            <property name="ignoredAnnotations"
                      value="After, AfterClass, Before, BeforeClass, Test, Property, Override"/>
        </module>
        <module name="FinalClass"/>
        <!-- <module name="HideUtilityClassConstructor"/> -->
        <module name="InterfaceIsType"/>
        <module name="VisibilityModifier"/>

        <!-- Miscellaneous other checks -->
        <!-- module name="ArrayTypeStyle"/-->
        <module name="UpperEll"/>
        <module name="Indentation">
            <property name="caseIndent" value="0"/>
            <property name="lineWrappingIndentation" value="8"/>
        </module>

        <!-- Checks for annotations -->
        <module name="MissingOverride"/>

        <!-- Filters -->
        <module name="SuppressionCommentFilter">
            <!-- This is useful when having deprecated public fields
                 which have been superseded by public accessors. -->
            <property name="offCommentFormat" value="ALLOW PUBLIC FIELDS"/>
            <property name="onCommentFormat" value="FORBID PUBLIC FIELDS"/>
            <property name="checkFormat" value="VisibilityModifier"/>
        </module>
    </module>
</module>