Compiling Grammars into Parsers

By default, the javacc goal will search for grammar files in the directory ${basedir}/src/main/javacc. The jjtree-javacc goal will expect to find *.jjt files in ${basedir}/src/main/jjtree and the jtb-javacc goal will expect to find *.jtb files in ${basedir}/src/main/jtb. Each of these can be configured to search other directories using the plugin configuration parameters as described in the respective goal documentation.

The next step is to configure your POM to call the plugin. The goals will normally run during the generate-sources phase of the build. Examples of how to configure your POM can be found on the various examples pages, reachable via the page menu. If you stick with the default values, the snippet below will suffice:

<project>
  ...
  <build>
    <plugins>
      <plugin>
        <groupId>org.codehaus.mojo</groupId>
        <artifactId>javacc-maven-plugin</artifactId>
        <version>3.1.1</version>
        <executions>
          <execution>
            <id>javacc</id>
            <goals>
              <goal>javacc</goal>
            </goals>
          </execution>
        </executions>
      </plugin>
    </plugins>
    ...
  </build>
  ...
</project>

Next run your build:

mvn generate-sources

For the javacc goal, Java source files will be generated to the directory target/generated-sources/javacc and this path will be added to your build as a source folder and automatically picked up by the next steps of the build (such as compilation).

Creating BNF Documentation from Grammars

The jjdoc goal is a tool for generating a site report. If the JavaCC Maven Plugin is added to the reporting section of your POM, the jjdoc goal will automatically be run when generating the project site. It will run the JJDoc tool once for each grammar file (*.jj) in your source directory. Each of these files, along with an index file containing a list of all the reports, will be created in the directory target/site/jjdoc. A default configuration looks like this:

<project>
  ...
  <reporting>
    <plugins>
      <plugin>
        <groupId>org.codehaus.mojo</groupId>
        <artifactId>javacc-maven-plugin</artifactId>
        <version>3.1.1</version>
      </plugin>
    </plugins>
    ...
  </reporting>
  ...
</project>

After the plugin is added to the reporting section of the POM, just run the following command to create the BNF documentation:

mvn site