apt maven plugin fail to generate Q classes - maven-plugin

Question

I am fixing a legacy project that uses Querydsl apt. For some reason the apt-maven-plugin started to fail. The only workaround I found was to use the alter ego maven-processor-plugin.
I have reinstalled maven, eclipse and M2E with not much success. The maven-apt-plugin is unable to create the Q classes under /target/generated-sources/metamodel.
edit: adding debug from maven
[DEBUG] Configuring mojo com.mysema.maven:apt-maven-plugin:1.0.8:process from pl
ugin realm ClassRealm[plugin>com.mysema.maven:apt-maven-plugin:1.0.8, parent: su
n.misc.Launcher$AppClassLoader#6d9bf996]
[DEBUG] Configuring mojo 'com.mysema.maven:apt-maven-plugin:1.0.8:process' with
basic configurator -->
[DEBUG] (s) logOnlyOnError = true
[DEBUG] (s) outputDirectory = C:\DEV\myproject\mainstuff\mainstuff-jpa\target\generate
d-sources\metamodel
[DEBUG] (s) pluginArtifacts = [com.mysema.maven:apt-maven-plugin:maven-plugin:
1.0.8:, org.sonatype.plexus:plexus-build-api:jar:0.0.7:compile, org.codehaus.ple
xus:plexus-utils:jar:1.5.8:compile, backport-util-concurrent:backport-util-concu
rrent:jar:3.1:compile, org.codehaus.plexus:plexus-interpolation:jar:1.11:compile
, junit:junit:jar:3.8.1:compile]
[DEBUG] (s) processor = com.mysema.query.apt.jpa.JPAAnnotationProcessor
[DEBUG] (s) project = MavenProject: com.yreham.mainstuff:mainstuff-jpa:1.0
# C:\DEV\myproject\mainstuff\mainstuff-jpa\pom.xml
[DEBUG] (s) sourceEncoding = ISO-8859-1
[DEBUG] -- end configuration --
[DEBUG] Using build context: org.sonatype.plexus.build.incremental.DefaultBuildC
ontext#27bb2f11
[ERROR] C:\DEV\myproject\mainstuff\mainstuff-jpa\src\main\java\com\yreham\mainstuff\j
pa\queries\InstancesQuery.java:40: error: cannot find symbol
import com.yreham.mainstuff.jpa.entity.QCIEntity;
Some details of the config m2e - Maven Integration for Eclipse 1.2.0.20120903-1050 org.eclipse.m2e.feature.feature.group Eclipse.org - m2e
java version "1.7.0_15"
Java(TM) SE Runtime Environment (build 1.7.0_15-b03)
Java HotSpot(TM) 64-Bit Server VM (build 23.7-b01, mixed mode)
(The target build is Java 1.6)
Here's the old pom XML
<plugin>
<groupId>com.mysema.maven</groupId>
<artifactId>apt-maven-plugin</artifactId>
<version>1.0.8</version>
<executions>
<execution>
<goals>
<goal>process</goal>
</goals>
<configuration>
<outputDirectory>${apt.target.dir}</outputDirectory>
processor>com.mysema.query.apt.jpa.JPAAnnotationProcessor</processor>
<logOnlyOnError>true</logOnlyOnError>
</configuration>
</execution>
</executions>
</plugin>
The new POM with bsc plugin
<plugin>
<groupId>org.bsc.maven</groupId>
<artifactId>maven-processor-plugin</artifactId>
<version>2.0.5</version>
<executions>
<execution>
<id>process</id>
<goals>
<goal>process</goal>
</goals>
<phase>generate-sources</phase>
<configuration>
<outputDirectory>${apt.target.dir}</outputDirectory>
<processors>
<processor>com.mysema.query.apt.jpa.JPAAnnotationProcessor</processor>
</processors>
</configuration>
</execution>
</executions>
<dependencies>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-jpamodelgen</artifactId>
<version>1.2.0.Final</version>
</dependency>
</dependencies>
</plugin>

Answer 1

Does your project build in command line?
If it doesn't, it'll most probably fail to build in eclipse too.
Now if CLI actually works, have you tried to install m2e-apt? It'll make annotation processing part of eclipse's incremental build process. See https://github.com/jbosstools/m2e-apt/ for more details.

Answer 2

Turns out it was a JPA configuration problem. I didn't see it was using an Hibernate layer on top Querydsl.
Since we moved to the Eclipse J2EE version and added M2E WTP http://www.eclipse.org/m2e-wtp/, the jpa module was correctly reconfigured.