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  <head>
    <title>Checkstyle ${projectVersion}</title>
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  <body>

    <section name="Overview">
      <p>
        Checkstyle is a development tool to help programmers write Java code
        that adheres to a coding standard. It automates the process of
        checking Java code to spare humans of this boring (but important)
        task. This makes it ideal for projects that want to enforce a coding
        standard.
      </p>

      <p>
        Checkstyle is highly configurable and can be made to support almost
        any coding standard. An example configuration files are supplied
        supporting the
        <a href="https://checkstyle.org/styleguides/sun-code-conventions-19990420/CodeConvTOC.doc.html">
          Sun Code Conventions</a>,
        <a href="styleguides/google-java-style-20180523/javaguide.html">
          Google Java Style</a>.
      </p>

      <p>
        A good example of a report that can be produced using Checkstyle and
        <a href="http://maven.apache.org/">Maven</a> can be <a
        href="http://maven.apache.org/plugins/maven-checkstyle-plugin/checkstyle.html">seen here</a>
          .
      </p>
    </section>

    <section name="Features">
      <p>
        Checkstyle can check many aspects of your source code.
        It can find class design problems, method design problems.
        It also has the ability to check code layout and formatting issues.
      </p>

      <p>
        For a detailed list of available checks please refer to the <a
        href="checks.html">Checks</a> page.
      </p>
    </section>

    <section name="Download">
      <p>
        The latest release of Checkstyle can be downloaded from <a
        href="https://github.com/checkstyle/checkstyle/releases/">the
        GitHub releases page</a>, or
        <a href="http://search.maven.org/#search|gav|1|g%3A%22com.puppycrawl.tools%22%20AND%20a%3A%22checkstyle%22">
            Maven central</a>.
      </p>

      <p>
        If you want to live on the bleeding edge, you can <a
        href="https://github.com/checkstyle/checkstyle">checkout</a>
        the current development code from GitHub and compile
        yourself. Or use <a href="https://jitpack.io/">jitpack.io</a> to build
        and get artifacts you need (you can even build your forked repo).
      </p>

    </section>

    <section name="Previous Version Documentation">
      <p>
        Current site contains documentation only for latest, released version.
        We only support this latest version. We highly recommend read latest documentation first.
        <br/>
        However, you might need documentation for previous releases because you are still using
        an older version and latest version describe some features that does not work for you.
        <br/>
        You can find documentation for most old versions using a URL format like
        https://checkstyle.sourceforge.io/version/X.X where "X.X" is the version number.<br/>
        Example:
        <a href="https://checkstyle.sourceforge.io/version/6.18/">
          https://checkstyle.sourceforge.io/version/6.18
        </a>
        for version 6.18.
      </p>
    </section>

    <section name="Backport">
      <p>
        Since Checkstyle 7, some users have been unable to continue upgrading to newer versions
        of the utility because of the new JDK 1.8 compile requirement. The development team doesn't
        have the resources to keep updating the utility for older JDKs for those that can't
        work with the latest version.
      </p>
      <p>
        However, some members of the community have created an unofficial backport of the latest
        Checkstyle releases to be run with JDKs as old as 1.6. If you wish to continue using new
        Checkstyle versions on older JDKs, we recommend you either checkout the
        <a href="https://github.com/rnveach/checkstyle-backport-jre6">github site</a> or the
        <a href="https://rnveach.github.io/checkstyle-backport-jre6/">documentation site</a> on how
        to use the backport version of the utility, in place of the official Checkstyle version.
      </p>
    </section>

    <section name="Development Cycle">
      <p>
        <b>Releases will happen at the end of each month</b>
        if functional changes exist in the
        <a href="https://github.com/checkstyle/checkstyle/commits/master">
            master branch of our repo</a>.
        For the exact day, please follow our
        <a href="https://github.com/checkstyle/checkstyle/milestones">milestones</a>.
      </p>
      <p>
        Checkstyle is not using Semantic Versioning
        (<a href="https://github.com/checkstyle/checkstyle/issues/3709">reasons in issue #3709</a>)
      </p>
    </section>

    <section name="Limitations">
      <p>
        Checkstyle is a single file static analysis tool, for more details please read
        the full list of <a href="writingchecks.html#Limitations">limitations</a>.
      </p>
    </section>

    <section name="Related Tools">
      <p>
        Checkstyle is most useful if you integrate it into your build process or
        your development environment. The distribution includes:
      </p>

      <ul>
        <li>An <a href="anttask.html">Ant task</a>.</li>
        <li>A <a href="cmdline.html">command line</a> interface (CLI).</li>
      </ul>

      <p>
        Additionally plug-ins are written by third-parties. Some of them are
        still based on the Checkstyle 2.4 release, although there have been
        many improvements since then. The known plug-ins are:
      </p>

      <subsection name="Active Tools" >
          <div class="wrapper">
              <table>
                  <tr>
                      <th>IDE / Build tool</th>
                      <th>Main/Initial Author</th>
                      <th>Available from</th>
                      <th>Remarks</th>
                  </tr>
                  <tr>
                      <td>
                          <a href="https://www.atlassian.com/software/bitbucket">
                              Bitbucket Server</a>
                      </td>
                      <td>Stephan Bechter</td>
                      <td>
                          <a href="https://marketplace.atlassian.com/apps/1214095/checkstyles-for-bitbucket-server">
                              Checkstyle for Bitbucket Server
                          </a>
                      </td>
                      <td/>
                  </tr>
                  <tr>
                      <td>
                          <a href="https://www.codacy.com/">Codacy</a>
                      </td>
                      <td>João Machado</td>
                      <td>
                          <a href="https://github.com/codacy/codacy-checkstyle/">
                              codacy-checkstyle
                          </a>
                      </td>
                      <td>
                          Provides analysis per commit and per pull request. Supports CheckStyle
                          config files.
                      </td>
                  </tr>
                  <tr>
                      <td><a href="https://www.eclipse.org/">Eclipse/RAD/RDz</a></td>
                      <td>Christian Wulf</td>
                      <td>
                         <a href="https://github.com/ChristianWulf/qa-eclipse-plugin">
                            Lightweight Eclipse Plugin for Quality Assurance Tools
                         </a>
                      </td>
                      <td>Alternative to the Eclipse-CS plugin.
                         Allows to use custom checks directly without providing
                         an Eclipse Fragment plugin for that purpose.
                      </td>
                  </tr>
                  <tr>
                      <td><a href="https://www.eclipse.org/">Eclipse/RAD/RDz</a></td>
                      <td>David Schneider</td>
                      <td>
                          <a href="https://checkstyle.org/eclipse-cs/#!/">Eclipse-CS Home Page</a>
                      </td>
                      <td>
                          In 2007 was awarded
                          <a href="https://www.eclipse.org/org/press-release/20070306eclipsecommunityawards.php">
                              Best Open Source Eclipse-based Developer tool
                          </a>.
                      </td>
                  </tr>
                  <tr>
                      <td><a href="https://gradle.org">Gradle</a></td>
                      <td>Hans Dockter (initial author)</td>
                      <td>Checkstyle supported out of the box</td>
                      <td><a href="https://docs.gradle.org/current/userguide/checkstyle_plugin.html">
                          Gradle Checkstyle docs</a></td>
                  </tr>
                  <tr>
                      <td><a href="https://www.jetbrains.com/idea/">IntelliJ IDEA</a></td>
                      <td>James Shiell</td>
                      <td>
                          <a href="https://github.com/jshiell/checkstyle-idea">
                              Checkstyle-idea Project Page</a>
                      </td>
                      <td>Provides real-time and on-demand scanning.</td>
                  </tr>
                  <tr>
                      <td><a href="https://www.jgrasp.org/">jGRASP</a></td>
                      <td>Larry Barowski</td>
                      <td><a href="https://www.jgrasp.org/">jGRASP Home Page</a></td>
                      <td/>
                  </tr>
                  <tr>
                      <td><a href="https://www.eclipse.org/">Eclipse/RAD/RDz</a></td>
                      <td>Roman Ivanov</td>
                      <td>
                          <a href="https://github.com/sevntu-checkstyle">Project Page</a>
                      </td>
                      <td>
                          Extension for Eclipse-CS plugin and also an incubator for
                          Checkstyle checks that are not present in main stream of
                          Checkstyle. See the
                          <a href="https://github.com/sevntu-checkstyle/sevntu.checkstyle/wiki">Wiki</a>
                          and
                          <a href="http://sevntu-checkstyle.github.io/sevntu.checkstyle/">Blog</a>
                          .
                      </td>
                  </tr>
                  <tr>
                      <td><a href="https://www.eclipse.org/">Eclipse/RAD/RDz</a></td>
                      <td>Jan Burkhardt</td>
                      <td>
                          <a href="https://github.com/bjrke/JSR305CheckstylePlugin">Project Page</a>
                      </td>
                      <td>
                          Extension for Eclipse-CS plugin which ensures nullness annotations on
                          methods and constructors (JSR305).
                      </td>
                  </tr>
                  <tr>
                      <td><a href="https://bitbucket.org/atlassian/bamboo-checkstyle-plugin">
                          Bamboo Checkstyle plug-in</a></td>
                      <td>Atlassian (formerly by Ross Rowe and Stephan Paulicke)</td>
                      <td><a href="https://bitbucket.org/atlassian/bamboo-checkstyle-plugin">
                          Bamboo Checkstyle plug-in Home Page</a></td>
                      <td>An add-on that will parse and record CheckStyle reports and report your
                          style violations over time.</td>
                  </tr>
                  <tr>
                      <td>
                          <a href="https://codeclimate.com/">Code Climate</a>
                      </td>
                      <td>Sivakumar Kailasam</td>
                      <td>
                          <a href="https://github.com/sivakumar-kailasam/codeclimate-checkstyle">
                              codeclimate-checkstyle
                          </a>
                      </td>
                      <td/>
                  </tr>
                  <tr>
                      <td><a href="https://wiki.jenkins.io/display/JENKINS/Checkstyle+Plugin">Jenkins
                      Checkstyle plug-in</a></td>
                      <td/>
                      <td><a href="https://wiki.jenkins.io/display/JENKINS/Checkstyle+Plugin">Jenkins
                      Checkstyle plug-in Home Page</a></td>
                      <td>This plug-in is supported by the Static Analysis Collector plug-in that
                      collects different analysis results and shows the results in aggregated trend
                      graphs.</td>
                  </tr>
                  <tr>
                      <td><a href="http://maven.apache.org/">Maven</a></td>
                      <td>Vincent Massol</td>
                      <td>Checkstyle supported out of the box</td>
                      <td><a href="http://maven.apache.org/plugins/maven-checkstyle-plugin/checkstyle.html">
                          example report</a></td>
                  </tr>
                  <tr>
                      <td><a href="http://tide.olympe.in/">tIDE</a></td>
                      <td/>
                      <td>Built in</td>
                      <td/>
                  </tr>
                  <tr>
                      <td><a href="https://netbeans.org/">NetBeans</a></td>
                      <td>Petr Hejl</td>
                      <td>
                          <a href="https://www.sickboy.cz/checkstyle/">Checkstyle Beans</a>
                      </td>
                      <td>
                          Problems with source code are displayed as annotations of
                          the source
                      </td>
                  </tr>
                  <tr>
                      <td><a href="https://netbeans.org/">NetBeans</a></td>
                      <td/>
                      <td>
                          <a href="http://sqe-team.github.io">Software Quality Environment (SQE)</a>
                      </td>
                      <td/>
                  </tr>
                  <tr>
                      <td><a href="https://www.sonarqube.org/">SonarQube</a></td>
                      <td>Freddy Mallet (initial author)</td>
                      <td><a href="https://github.com/checkstyle/sonar-checkstyle">
                          Checkstyle SonarQube repository</a></td>
                      <td><a href="https://sonarcloud.io/projects">Demo site of SonarQube</a></td>
                  </tr>
                  <tr>
                      <td><a href="http://www.jedit.org/">jEdit</a></td>
                      <td>Todd Papaioannou</td>
                      <td><a href="http://plugins.jedit.org/plugins/?CheckStylePlugin">
                          JEdit CheckStylePlugin</a></td>
                      <td/>
                  </tr>
                  <tr>
                      <td><a href="https://www.scm-manager.org/">SCM-Manager</a></td>
                      <td/>
                      <td><a href="http://plugins.scm-manager.org/scm-plugin-backend/page/index.html">
                          SCM-Manager Plugin Page</a></td>
                      <td/>
                  </tr>
                  <tr>
                      <td><a href="https://www.jetbrains.com/idea/">IntelliJ IDEA</a></td>
                      <td>Jakub Slawinski</td>
                      <td>
                          <a href="https://plugins.jetbrains.com/plugin/4594-qaplug">QAPlug</a>
                      </td>
                      <td>Provides quality assurance features.</td>
                  </tr>
                  <tr>
                      <td><a href="https://www.jarchitect.com">JArchitect</a></td>
                      <td/>
                      <td><a href="https://www.jarchitect.com">JArchitect Home Page</a></td>
                      <td>Imports XML result files from CheckStyle.</td>
                  </tr>
                  <tr>
                      <td><a href="https://www.scala-sbt.org/">SBT</a></td>
                      <td>Andrew Johnson</td>
                      <td><a href="https://github.com/etsy/sbt-checkstyle-plugin">
                          sbt-checkstyle-plugin Project Page</a></td>
                      <td>SBT plugin for running Checkstyle on Java source files in an SBT
                        project</td>
                  </tr>
                  <tr>
                      <td><a href="https://github.com/nidi3/code-assert">code-assert</a></td>
                      <td>Stefan Niederhauser</td>
                      <td><a href="https://github.com/nidi3/code-assert#checkstyle-checks">
                          code-assert</a></td>
                      <td>Assert that the java code of a project satisfies certain checks. Launch
                          checkstyle validation from UTs</td>
                  </tr>
                  <tr>
                      <td><a href="http://jdee.sourceforge.net/">Emacs JDE</a></td>
                      <td>Markus Mohnen</td>
                      <td>Part of the standard JDEE distribution -
                          <a href="https://github.com/jdee-emacs/jdee"/>
                      </td>
                      <td><a href="https://github.com/jdee-emacs/jdee/blob/master/jdee-checkstyle.el">
                          configuration could be seen at jdee-checkstyle.el</a></td>
                  </tr>
                  <tr>
                      <td><a href="https://code.visualstudio.com/">Visual Studio Code</a></td>
                      <td>Sheng Chen</td>
                      <td><a href="https://marketplace.visualstudio.com/items?itemName=shengchen.vscode-checkstyle">
                          vscode-checkstyle</a></td>
                      <td>Checkstyle for Microsoft Visual Studio Code</td>
                  </tr>
              </table>
          </div>
      </subsection>

      <subsection name="Inactive / Old Tools" >
          <div class="wrapper">
              <table>
                  <tr>
                      <th>IDE / Build tool</th>
                      <th>Main/Initial Author</th>
                      <th>Available from</th>
                      <th>Remarks</th>
                  </tr>
                  <tr>
                      <td><a href="http://qalab.sourceforge.net/">QALab</a></td>
                      <td>Benoit Xhenseval</td>
                      <td><a href="http://qalab.sourceforge.net/">QALab Home Page</a></td>
                      <td>Supports tracking Checkstyle statistics over time.</td>
                  </tr>
                  <tr>
                      <td><a href="https://vim.sourceforge.io/">Vim editor</a></td>
                      <td>Xandy Johnson</td>
                      <td><a href="https://vim.sourceforge.io/scripts/script.php?script_id=448">
                          Plugin Homepage</a></td>
                      <td>Vim file-type plug-in</td>
                  </tr>
              </table>
          </div>
      </subsection>

      <p>
        If you have written a plugin for other IDEs, please let us know, so we
        can provide a link here.
      </p>

    </section>

  </body>
</document>
