checkstyle.xml

<?xml version="1.0"?>
<!--

    Copyright 2015-2016 Maven Source Dependencies
    Plugin contributors as indicated by the @author tags.

    Licensed 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
    "-//Puppy Crawl//DTD Check Configuration 1.2//EN"
    "http://www.puppycrawl.com/dtds/configuration_1_2.dtd">

<module name="Checker">

  <module name="FileTabCharacter">
    <property name="eachLine" value="true" />
  </module>

  <module name="RegexpSingleline">
    <!-- \s matches whitespace character, $ matches end of line. -->
    <property name="format" value="\s+$" />
    <property name="message" value="Line has trailing spaces." />
  </module>

  <!-- Enforce UNIX line endings. -->
  <module name="RegexpMultiline">
    <property name="format" value="\r\n" />
    <property name="maximum" value="0" />
    <property name="message" value="Line ends with Windows-style \r\n characters. Please use UNIX-style \n end of lines." />
  </module>

  <module name="TreeWalker">

    <property name="cacheFile" value="${checkstyle.cache.file}" />

    <!-- Checks for imports -->
    <module name="AvoidStarImport">
      <property name="allowStaticMemberImports" value="true" />
    </module>
    <module name="RedundantImport" />

    <module name="UnusedImports">
      <property name="processJavadoc" value="true" />
    </module>

    <module name="ImportOrder">
      <property name="groups" value="/^javax?\./,org,com" />
      <property name="ordered" value="true" />
      <property name="separated" value="true" />
      <property name="option" value="top" />
    </module>

    <module name="IllegalImport">
      <property name="illegalPkgs" value="junit.framework" />
    </module>

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

    <!-- Checks for blocks. You know, those {}'s -->
    <module name="LeftCurly">
      <property name="option" value="eol" />
      <property name="tokens" value="CLASS_DEF,CTOR_DEF,INTERFACE_DEF,METHOD_DEF,LITERAL_SWITCH,STATIC_INIT" />
    </module>

    <!-- Checks for common coding problems -->
    <!-- Disabled until http://sourceforge.net/tracker/?func=detail&aid=2843447&group_id=29721&atid=397078
      is fixed -->
    <!--<module name="DoubleCheckedLocking"/> -->
    <module name="EmptyStatement" />
    <module name="EqualsHashCode" />
    <module name="IllegalInstantiation" />

    <!-- Miscellaneous other checks. -->
    <module name="UpperEll" />
    <module name="PackageAnnotation" />
    <module name="CovariantEquals" />
    <module name="ArrayTypeStyle" />

  </module>

</module>