How to enhance a class from a separate jar at build time with openJPA?

Question

I am trying to enhance an Entity class coming from another Jar using maven plugin openjpa-maven-plugin and unfortunately I didn't find a correct way to do it.

I have one class MyPojo from module MyDomain packaged in jar my-domain.jar :

public class MyPojo {

private Long id;

...

}

In my second project MyJpa packaging my-jpa.jar, it depends on module my-domain.jar, and Maven is configured to use Build Time OpenJPA Enhancer with the following:

<plugin>
            <groupId>org.apache.openjpa</groupId>
            <artifactId>openjpa-maven-plugin</artifactId>
            <configuration>
                <includes>**/entity/*.class</includes>
                <addDefaultConstructor>true</addDefaultConstructor>
                <enforcePropertyRestrictions>true</enforcePropertyRestrictions>
            </configuration>
            <executions>
                <execution>
                    <id>enhancer</id>
                    <phase>process-classes</phase>
                    <goals>
                        <goal>enhance</goal>
                    </goals>
                </execution>
            </executions>
            <dependencies>
                <dependency>
                    <groupId>org.apache.openjpa</groupId>
                    <artifactId>openjpa</artifactId>
                    <version>2.3.0</version>
                </dependency>
            </dependencies>
        </plugin>

and I am using an XML mapping orm.xml declared in persistence.xml :

            ... 
    <provider>org.apache.openjpa.persistence.PersistenceProviderImpl</provider>

    <mapping-file>META-INF/orm.xml</mapping-file>

 ...

and with the orm.xml that looks like :

    <entity class="MyPojo" access="FIELD">
    <table name="MYPOJO"/>
    <attributes>
        <id name="id">
            <generated-value strategy="AUTO"/>
        </id>
    </attributes>
    </entity>

Running mvn install gives the following error :

This configuration disallows runtime optimization, but the following listed types were not enhanced at build time or at class load time with a javaagent:

When I move the class MyPojo into the project MyJpa (instead of the project MyDomain), it works.

So my question is : what do I need to configure in order to be able to enhance at build time the class MyPojo coming from an external Jar ?

Answer 1

what do I need to configure in order to be able to enhance at build time the class MyPojo coming from an external Jar ?

If I understand your question correctly, you can't enhance a class that lives inside of a jar at build time. If you want to enhance in this way, you need to unjar the class, enhance, then rejar.