Eclipse – M2E and having maven generated source folders as eclipse source folders

eclipsem2em2eclipsemaven

I have a maven project in eclipse and have maven goals that run annotation processors to generate code. The output folder for this code is target/generated-sources/apt.

In order for eclipse to see this generated code I need to add target/generated-sources/apt as a source folder to the eclipse project.

However, this causes there to be an error of type "Maven Configuration Problem" saying

Project configuration is not up-to-date with pom.xml. Run project
configuration update

I think I understand why this is the case as eclipse has a different set of source folders to maven's set. But I need this different set, as I need eclipse to be able to see the generated source folders…

When doing a pure maven built, these source folders will be included in the build, by maven.

btw, I have upgraded to the official eclipse release of the maven eclipse plugin, m2e 1.0 – what used to be m2eclipse. I'd like to see if I can find a work around/solution to this with the m2e plugin before I have to go back to the old m2eclipse version.

Best Answer

You need to attach the source directory with the build-helper-plugin.

Like so:

 <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}/generated-sources/java/</source>
                </sources>
            </configuration>
        </execution>
    </executions>
 </plugin>

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