The following examples describe the basic usage of the Checkstyle Plugin.
To generate the Checkstyle report as part of the Project Reports, add the Checkstyle Plugin in the <reporting> section of your pom.xml.
<project>
  ...
   <reporting>
      <plugins>
        <plugin>
          <groupId>org.apache.maven.plugins</groupId>
          <artifactId>maven-checkstyle-plugin</artifactId>
          <version>2.14</version>
          <reportSets>
            <reportSet>
              <reports>
                <report>checkstyle</report>
              </reports>
            </reportSet>
          </reportSets>
        </plugin>
      </plugins>
    </reporting>
  ...
</project>
Then, execute the site phase to generate the report.
mvn site
You can also generate the Checkstyle report by explicitly executing the checkstyle:checkstyle goal from the command line. You are not required to specify the Checkstyle Plugin in your pom.xml unless you want to use a specific configuration.
mvn checkstyle:checkstyle
If you want to report to the console or fail the build, you must add an execution of checkstyle::check to the <build> element and configure any options that you need.
(Note in that for Maven 3, as per Maven 3 Compatibility Notes, in Maven 3, options you set in the <reporting> element do not have any effect on executions in the <build> element.)
For example:
 <plugin>
   <groupId>org.apache.maven.plugins</groupId>
   <artifactId>maven-checkstyle-plugin</artifactId>
   <version>2.14</version>
   <executions>
     <execution>
       <id>validate</id>
       <phase>validate</phase>
       <configuration>
         <configLocation>checkstyle.xml</configLocation>
         <encoding>UTF-8</encoding>
         <consoleOutput>true</consoleOutput>
         <failsOnError>true</failsOnError>
         <linkXRef>false</linkXRef>
       </configuration>
       <goals>
         <goal>check</goal>
       </goals>
     </execution>
   </executions>
 </plugin>