When building a Maven site, why does my annotation processor run twice and break the build?

Question

I have a build that uses the annotation processor plugin to generate JPA criteria classes with the Hibernate JPA 2 Metamodel Generator.

This works well when doing a normal mvn clean package, but when I build the site, it fails:

[INFO] --- maven-processor-plugin:2.1.0:process (generate-jpa-metamodel) @ phtool-api ---
[INFO] Source directory: C:\jp\esv-projects\phtool\phtool-api\target\generated-sources\jpa added
[INFO] javac option: -cp
[INFO] javac option: ...
[INFO] javac option: -proc:only
[INFO] javac option: -processor
[INFO] javac option: org.hibernate.jpamodelgen.JPAMetaModelEntityProcessor
[INFO] javac option: -d
[INFO] javac option: C:\jp\esv-projects\phtool\phtool-api\target\classes
[INFO] javac option: -s
[INFO] javac option: C:\jp\esv-projects\phtool\phtool-api\target\generated-sources\jpa
[INFO] diagnostic Note: Hibernate JPA 2 Static-Metamodel Generator 1.2.0.Final
[INFO] diagnostic C:\jp\projects\phtool\phtool-api\target\generated-sources\jpa\phtool\impl\resource\ImageImpl_.java:10: error: duplicate c
lass: phtool.impl.resource.ImageImpl_

I noticed that the plugin runs twice during the site generation, but I don't know why. Perhaps it's a known Javadoc plugin bug?

With `mvn clean site-deploy -Pfull-site-no-java-ncss`: The profile used contains the whole configuration for the site plugin. — eerriicc, Feb 07 '13 at 15:50
Did you resolve this? I'm having the same problem and haven't found a solution. — Jonas, Apr 17 '13 at 09:36

score 0 · Accepted Answer · answered Aug 05 '13 at 07:34

The problem is solved now, through changes in the parent POM. I can't exactly tell what change solved the problem, but here are the relevant versions within my POM:

      <groupId>org.bsc.maven</groupId>
      <artifactId>maven-processor-plugin</artifactId>
      <version>2.2.4</version>

      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-compiler-plugin</artifactId>
      <version>3.1</version>

      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-site-plugin</artifactId>
      <version>3.3</version>

      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-javadoc-plugin</artifactId>
      <version>2.9</version>

Note that the version of the Javadoc plugin hasn't changed!

When building a Maven site, why does my annotation processor run twice and break the build?

1 Answers1