| ------ |
| Using Custom Checkstyle Property Expansion Definitions |
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| 2006-07-21 |
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| |
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| |
| |
| Using Custom Checkstyle Property Expansion Definitions |
| |
| Custom {{{https://checkstyle.org/config.html#Properties}property expansion definitions}} |
| for the Checker can be defined. |
| |
| Checkstyle uses the property expansion mechanism to allow injection of specific values into a pre-defined |
| Checker configuration. Using property expansion alone is an insufficient means to customize the checks |
| performed by Checkstyle. |
| |
| Example: <<<checkstyle.xml>>> - only checks the package name in use to ensure that it conforms to the |
| desired scheme, but allows for users of this Checker to specify their own projectname. |
| |
| +-----+ |
| <?xml version="1.0" ?> |
| |
| <!DOCTYPE module PUBLIC |
| "-//Checkstyle//DTD Checkstyle Configuration 1.2//EN" |
| "https://checkstyle.org/dtds/configuration_1_2.dtd"> |
| |
| <module name="Checker"> |
| <module name="TreeWalker"> |
| <module name="PackageName"> |
| <property name="format" |
| value="com\.example\.$\{projectname\}(\.[a-z][a-zA-Z0-9]+)*$"/> |
| </module> |
| </module> |
| </module> |
| +-----+ |
| |
| Example: <<<pom.xml>>> - Specifies the <<<projectname>>> property expansion that Checkstyle will use when |
| encountering such a variable in the above Checker configuration. |
| |
| +-----+ |
| <project> |
| ... |
| <reporting> |
| <plugins> |
| <plugin> |
| <groupId>org.apache.maven.plugins</groupId> |
| <artifactId>maven-checkstyle-plugin</artifactId> |
| <version>${project.version}</version> |
| <configuration> |
| <configLocation>checkstyle.xml</configLocation> |
| <propertyExpansion> |
| projectname=whizbang |
| anotherProperty=bazinga |
| </propertyExpansion> |
| </configuration> |
| </plugin> |
| </plugins> |
| </reporting> |
| ... |
| </project> |
| +-----+ |
| |
| The property expansion information can also come from a location using the <<<propertiesLocation>>> |
| parameter as shown below. The <<<propertiesLocation>>> can point to a URL, File or build classpath resource reference. |
| |
| +-----+ |
| <project> |
| ... |
| <reporting> |
| <plugins> |
| <plugin> |
| <groupId>org.apache.maven.plugins</groupId> |
| <artifactId>maven-checkstyle-plugin</artifactId> |
| <version>${project.version}</version> |
| <configuration> |
| <configLocation>checkstyle.xml</configLocation> |
| <propertiesLocation>${basedir}/checkstyle.properties</propertiesLocation> |
| </configuration> |
| </plugin> |
| </plugins> |
| </reporting> |
| ... |
| </project> |
| +-----+ |