maven-jar-plugin refuses to include META-INF/persistence.xml !

[Tommy Svensson]

Hello maven fans,

I've become slightly balder today. I've been tearing my hair over why JPA keeps 
insisting it cannot find my persistence unit. Everything in my persistence.xml 
file is correct I've checked it over an over. 

I've just discovered that the problem is not in the JPA provider (tried both 
EclipseLink and OpenJPA), but in Maven!!!

Maven just refuses to include META-INF/persistence.xml in the jar no matter 
what I do! It resides in src/main/resources/META-INF. After building it is also 
in target/classes/META-INF along with MANIFEST.MF, but it is missing in the jar 
file. 

I googled and someone suggested this (yes, I'm not alone with this problem):

        <resources>
            <resource>
                <filtering>false</filtering>
                <directory>${basedir}/src/main/resources</directory>
                <includes>
                    <include>META-INF/persistence.xml</include>
                </includes>
            </resource>
        </resources>

That however had no effect what so ever. Next I tried this:

            <plugin>
                <artifactId>maven-jar-plugin</artifactId>
                <configuration>
                    <includes>
                        <include>META-INF/persistence.xml</include>
                    </includes>
                    <archive>
                        
<manifestFile>${project.build.outputDirectory}/META-INF/MANIFEST.MF</manifestFile>
                    </archive>
                </configuration>
            </plugin>

That didn't help either. Then I found at codehaus that this was a bug and that 
it was fixed in version 2.1 of the maven-jar-plugin. So I tried to add version 
to the plugin specification. Version 2.4 was the latest I found:

            <plugin>
                <artifactId>maven-jar-plugin</artifactId>
                <version>2.4</version>
                <configuration>
                    <includes>
                        <include>META-INF/persistence.xml</include>
                    </includes>
                    <archive>
                        
<manifestFile>${project.build.outputDirectory}/META-INF/MANIFEST.MF</manifestFile>
                    </archive>
                </configuration>
            </plugin>

That didn't work either. I'm out of ideas and my fingers hurt from all the 
googling. Do anyone have any idea how to solve this truly annoying problem ?

I can add that I'm also using the Apache Felix maven-bundle-plugin. I don't 
know if it can affect this behavior. 

Anyhow, any suggestions are appreciated. Currently I have to manually jar my 
project. 

Regards,
Tommy Svensson