No Persistence provider for EntityManager named with eclipselink

Question

I have a small project running fine in Eclipse. However when I package it in a jar it will fail with No Persistance provider.

I have tried with adding eclipselink as a maven dependency, external jar file and just as a normal project dependency in Eclipse. I have also tried to packaged with extract and package required libraries with no difference.

Worth noting is that the Jersey dependencies will work just fine and call the server with no problem. so those dependencies are working in the .jar file.

The Persistence.xml is located in
project/src/META-INF/persistence.xml

I have tried removing one of the persistance-unit without change.

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
    <persistence-unit name="TestMDB" transaction-type="RESOURCE_LOCAL">
        <class>com.sg.db.entity.Result</class>
        <properties>
            <property name="javax.persistence.jdbc.url" value="jdbc:ucanaccess://viking.mdb"/>
            <property name="javax.persistence.jdbc.driver" value="net.ucanaccess.jdbc.UcanaccessDriver"/>
        </properties>
    </persistence-unit>
    <persistence-unit name="TestMDBLive" transaction-type="RESOURCE_LOCAL">
        <class>com.sg.db.entity.Result</class>
        <properties>
            <property name="javax.persistence.jdbc.url" value="jdbc:ucanaccess://c:/Viking2001/DataBas/Viking.mdb"/>
            <property name="javax.persistence.jdbc.driver" value="net.ucanaccess.jdbc.UcanaccessDriver"/>
        </properties>
    </persistence-unit>
</persistence>

The project is a Maven project. It has external dependencies that I added with

<dependency>
 <groupId>ucanaccess</groupId>
 <artifactId>ucanaccess</artifactId>
 <scope>system</scope>
 <version>3.0.1</version>
 <systemPath>${project.basedir}/lib/ucanaccess-3.0.1.jar</systemPath>
</dependency>


No Persistence provider for EntityManager named TestMDBLive
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:85)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:54)

It will fail at the factory creation in the init()

public void init() {

        //Setup database connection
        try {
            factory = Persistence.createEntityManagerFactory(PERSISTENCE_UNIT_NAME);
            em = factory.createEntityManager();

        } catch (Exception ex) {
            ex.printStackTrace();       }

    }

Try putting `org.eclipse.persistence.jpa.PersistenceProvider` in your persistence unit configurations. — Predrag Maric, Oct 05 '15 at 09:52
No change doing that. Still same error message. do I need a MANIFEST.MF configured to point to persistence.xml ? — user2130951, Oct 05 '15 at 09:56
Where is `persistence.xml` located in the deployed jar file? it should be at `/META-INF/persistence.xml`. If you have put it under `project/src/META-INF` then it's probably misplaced in the resulting jar. — Predrag Maric, Oct 05 '15 at 10:10

score 0 · Answer 1 · answered Oct 05 '15 at 09:17

0

Try packaging your application with maven assembly plugin.

This will ensure that all dependencies are correctly placed into the jar archive

answered Oct 05 '15 at 09:17

WeMakeSoftware

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Tried it but it will end up not packaging the external jars that are part of the pom.xml – user2130951 Oct 05 '15 at 09:42
how do you launch the assembly plugin? – WeMakeSoftware Oct 05 '15 at 10:02
With mvn package from the prompt no errors in output. – user2130951 Oct 05 '15 at 10:03
after configuring the plugin you should run it like this: mvn clean assembly:single . More info here: http://stackoverflow.com/questions/13615634/maven-build-assembly-with-dependencies – WeMakeSoftware Oct 05 '15 at 10:06

score 0 · Accepted Answer · answered Oct 05 '15 at 11:37

I had originally created a normal project that I used configure on and converted it to a maven project.

I re-created the project as a maven project from scratch and copied the resources over. After that the project ran correctly and eclipselink was also included.

To note is that the persistence.xml should still be in src/mail/java/META.INF with no need to move it.

No Persistence provider for EntityManager named with eclipselink

2 Answers2