Proper Lifecycle Order For Annotation Processing In Maven

I’m currently working on a java project where I need to generate and compile JPA metamodel classes as part of the build. I did some research and found an answer here: Generate the JPA metamodel files using maven-processor-plugin – What is a convenient way for re-generation? that seems like a reasonable solution. The problem is, my project also contains some groovy classes that need to be compiled alongside the java. If I enable the maven-processor-plugin, the maven build will fail as soon as it encounters a java class that depends on a groovy class. Looking at the console output, I can see that maven-processor-plugin is running before the groovy compiler, so those groovy classes have not had a chance to be compiled.

Does anyone know if there is a good way to handle this? Is there some way to break the compilation process up into stages so that I can control what gets processed when?

Here is a snippet of my pom.xml:

<build>
    <plugins>
        <plugin>
            <artifactId>maven-compiler-plugin</artifactId>              
            <configuration>
                <showWarnings>false</showWarnings>
                <compilerId>groovy-eclipse-compiler</compilerId>
               <compilerArgument>-proc:none</compilerArgument>
            </configuration>
            <dependencies>
                <dependency>
                    <groupId>org.codehaus.groovy</groupId>
                    <artifactId>groovy-eclipse-compiler</artifactId>
                    <version>3.6.0-03</version>
                  </dependency>
                  <dependency>
                    <groupId>org.codehaus.groovy</groupId>
                    <artifactId>groovy-eclipse-batch</artifactId>
                    <version>3.0.7-02</version>
                  </dependency>
            </dependencies>
        </plugin>
        <plugin>
            <groupId>org.bsc.maven</groupId>
            <artifactId>maven-processor-plugin</artifactId>
           <version>4.5-jdk8</version>
            <executions>
                <execution>
                    <id>process</id>
                    <goals>
                        <goal>process</goal>
                    </goals>
                    <phase>generate-sources</phase>
                    <configuration>
                        <outputDirectory>${project.build.directory}/../src/main/generated-sources/java/jpametamodel</outputDirectory>
                        <processors>
                            <processor>org.hibernate.jpamodelgen.JPAMetaModelEntityProcessor</processor>
                        </processors>
                        <overwrite>true</overwrite>
                    </configuration>
                </execution>
            </executions>
            <dependencies>
                <dependency>
                    <groupId>org.hibernate</groupId>
                    <artifactId>hibernate-jpamodelgen</artifactId>                     
                    <version>5.3.13.Final</version>                     
                </dependency>                  
            </dependencies>
        </plugin>
        <plugin>
            <groupId>org.codehaus.mojo</groupId>
            <artifactId>build-helper-maven-plugin</artifactId>          
            <executions>
              <execution>
                <id>add-source</id>
                <phase>generate-sources</phase>
                <goals>
                  <goal>add-source</goal>
                </goals>
                <configuration> 
                  <sources>               
                    <source>${project.build.directory}/../src/main/generated-sources/java/jpametamodel</source>                
                  </sources>                
                </configuration>
              </execution>
            </executions>
          </plugin>       
    </plugins>
</build>

Answer

After a good bit of trial and error I finally found a solution that seems to work. maven-processor-plugin can use include/exclude filters to limit the scope of the files it looks at. I added an includes filter that restricts the processing to my domain classes. Now when I build it can process my annotated classes without getting hung up on the groovy files.

My final result ended up looking like this:

          <plugin>
                <groupId>org.bsc.maven</groupId>
                <artifactId>maven-processor-plugin</artifactId>
               <version>4.5-jdk8</version>
                <executions>
                    <execution>
                        <id>process</id>
                        <goals>
                            <goal>process</goal>
                        </goals>
                        <phase>generate-sources</phase>
                        <configuration>
                        <includes>
                            <include>com/tura/product/domain/*.java</include>
                        </includes>
                            <outputDirectory>${project.build.directory}/generated-sources/java</outputDirectory>
                            <processors>
                                <processor>org.hibernate.jpamodelgen.JPAMetaModelEntityProcessor</processor>
                            </processors>
                            <overwrite>true</overwrite>
                        </configuration>
                    </execution>
                </executions>
                <dependencies>
                    <dependency>
                        <groupId>org.hibernate</groupId>
                        <artifactId>hibernate-jpamodelgen</artifactId>                     
                        <version>5.3.13.Final</version>                     
                    </dependency>                  
                </dependencies>
            </plugin>