title: JPA Hibernate Metamodel generation through maven
body: <p>I followed the JPA modelgen <a href="http://docs.jboss.org/hibernate/jpamodelgen/1.0/reference/en-US/html_single/#d0e261">guide</a> and i was able to generate the canonical metamodel which i need. With this pom set up:</p>
  
  <pre><code>&lt;plugin&gt;
                  &lt;artifactId&gt;maven-compiler-plugin&lt;/artifactId&gt;
                  &lt;configuration&gt;
                      &lt;source&gt;1.6&lt;/source&gt;
                      &lt;target&gt;1.6&lt;/target&gt;
                      &lt;compilerArgument&gt;-proc:none&lt;/compilerArgument&gt;
                  &lt;/configuration&gt;
              &lt;/plugin&gt;
              &lt;plugin&gt;
                  &lt;groupId&gt;org.bsc.maven&lt;/groupId&gt;
                  &lt;artifactId&gt;maven-processor-plugin&lt;/artifactId&gt;
                  &lt;version&gt;2.0.6-redhat&lt;/version&gt;
                  &lt;executions&gt;
                      &lt;execution&gt;
                          &lt;id&gt;process&lt;/id&gt;
                          &lt;goals&gt;
                              &lt;goal&gt;process&lt;/goal&gt;
                          &lt;/goals&gt;
                          &lt;phase&gt;generate-sources&lt;/phase&gt;
                          &lt;configuration&gt;
                              &lt;outputDirectory&gt;target/metamodel&lt;/outputDirectory&gt;
                          &lt;/configuration&gt;
                      &lt;/execution&gt;
                  &lt;/executions&gt;
              &lt;/plugin&gt;
              &lt;plugin&gt;
                  &lt;groupId&gt;org.codehaus.mojo&lt;/groupId&gt;
                  &lt;artifactId&gt;build-helper-maven-plugin&lt;/artifactId&gt;
                  &lt;version&gt;1.3&lt;/version&gt;
                  &lt;executions&gt;
                      &lt;execution&gt;
                          &lt;id&gt;add-source&lt;/id&gt;
                          &lt;phase&gt;generate-sources&lt;/phase&gt;
                          &lt;goals&gt;
                              &lt;goal&gt;add-source&lt;/goal&gt;
                          &lt;/goals&gt;
                          &lt;configuration&gt;
                              &lt;sources&gt;
                                  &lt;source&gt;target/metamodel&lt;/source&gt;
                              &lt;/sources&gt;
                          &lt;/configuration&gt;
                      &lt;/execution&gt;
                  &lt;/executions&gt;
              &lt;/plugin&gt;
  </code></pre>
  
  <p>The generated source is properly created in the specified directory and i have to manually specify it as a source in the eclipse project class path to use it. When i trigger a maven  the logs show <code>cannot find symbol</code> or <code>duplicate class</code> and i still get successful build. So my question is, is this expected/correct behavior in creating the metamodel? or did i miss something in the cofig? Thanks</p>