In the previous section, we have seen how to generate the RAML documentation for the REST resource classes present in a JAX-RS application. In this section, you will learn how to generate the JAX-RS resources classes from an RAML documentation file. This feature is enabled via the raml-to-jaxrs-maven-plugin Maven plugin.

Perform the following steps for using RAML to the JAX-RS Maven plugin in a Maven project:

1. The raml-to-jaxrs-maven-plugin Maven plugin is available in the Maven central repository. If you do not see the latest release here, clone the Git repository available at https://github.com/mulesoft/raml-for-jax-rs and build the raml-for-jax-rs/raml-to-jaxrs project by executing mvn install.
2. Go to the maven project where you want to generate the JAX-RS resource classes from the RAML file. Include raml-to-jaxrs-maven-plugin in the project's pom.xml file. The <plugin> entry in the pom.xml file will look like the following:

<plugins> 
         <plugin>
                <groupId>org.raml.jaxrs</groupId>
                <artifactId>raml-to-jaxrs-maven-plugin</artifactId>
                <version>2.1.0</version>
                <configuration>
                    <ramlFile>${basedir}/src/main/resources/raml/department-resource.raml</ramlFile>
                    <resourcePackage>com.packtpub.rest.ch7.service</resourcePackage>
                    <modelPackage>com.packtpub.rest.ch7.model</modelPackage>
                    <jsonMapper>jackson2</jsonMapper>
                    <jsonMapperConfiguration>
                        <includeHashcodeAndEquals>true</includeHashcodeAndEquals>
                    </jsonMapperConfiguration>
                </configuration>
                <executions>
                    <execution>
                        <goals>
                            <goal>generate</goal>
                        </goals>
                        <phase>generate-sources</phase>
                    </execution>
                </executions>
            </plugin>  
 <!-- other plugins go here --> 
</plugins> 

3. Keep the RAML file that you want to convert into JAX-RS in the resources folder of the maven project. The plugin configuration lets you specify the RAML file via the <ramlFile> element.

4. Run mvn compile or mvn package, which will result in the generation of the JAX-RS resource classes for the RAML file present in the source folder. You can find the newly generated source files in the generated-sources folder under Maven's target folder.