I am currently working on an OSGi project on Felix (v4.0.3). I need to use JPA so I have installed the Apache Aries JPA bundles. I also installed OpenJPA and I need it to connect to a MySQL Database, using the MySQL Connector Bundle. Unfortunately it does not work, OpenJPA says it cannot find the MySQL JDBC class and I cannot figure out what's broken, maybe I am doing something wrong. I'll explain below what I installed precisely along with the persistence.xml file and the actual exception I get.
Here's the list of the Apache Aries bundles I installed :
- org.apache.aries.jpa.api-0.3.jar
- org.apache.aries.jpa.container.context-0.3.jar
- org.apache.aries.jpa.container-0.3.jar
- org.apache.aries.util-0.4.jar
I then installed the dependencies of those Apache Aries JPA bundles. I downloaded them from Springsource :
- com.springsource.javax.transaction-1.1.0.jar
- com.springsource.org.apache.log4j-1.2.16.jar
- com.springsource.slf4j.api-1.6.1.jar
- com.springsource.slf4j.log4j-1.6.1.jar
- javax.persistence_2.0.4.v201112161009.jar (this one is from EclipseLink in case it matters)
I also installed OpenJPA and all its dependencies. I found bundles 2 to 5 (commons-*) in the lib folder of the apache-openjpa-2.2.0 downloaded folder. I downloaded Serp here because the jar found in the lib folder wasn't an OSGi bundle. Finally I found the last two bundles (#7 and #8) in Springsource :
- openjpa-2.2.0.jar
- commons-collections-3.2.1.jar
- commons-dbcp-1.4.jar
- commons-lang-2.4.jar
- commons-pool-1.5.4.jar
- org.apache.servicemix.bundles.serp-1.13.1_4.jar
- com.springsource.javax.servlet-2.5.0.jar
- com.springsource.org.objectweb.asm-3.2.0.jar
Once I finally had OpenJPA installed, I still needed the MySQL JDBC Driver bundle, which I also got from the Springsource repository along with its commons-logging dependency :
- com.springsource.com.mysql.jdbc-5.1.6.jar
- com.springsource.org.apache.commons.logging-1.1.1.jar
Now at this point the list of bundles installed is getting quite large. I said I installed OpenJPA but it's only because I could not figure out how to use any other provider with Aries. I initially wanted to use EclipseLink but apparently Apache Aries does not detect it as a provider and according to this blog you have to make yet another bundle containing your own activator for Aries to notice EclipseLink. I tried it but it didn't work so I fell back on using OpenJPA instead.
So now I have two questions :
- How can I make OpenJPA notice my MySQL Bundle ?
OR alternatively :
- How can I make Apache Aries notice EclipseLink ?
Here's the persistence.xml file I use :
<persistence xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
version="2.0" xmlns="http://java.sun.com/xml/ns/persistence">
<persistence-unit name="userManager.model" transaction-type="RESOURCE_LOCAL">
<provider>org.apache.openjpa.persistence.PersistenceProviderImpl</provider>
<class>org.project.dao.entity.UserEntity</class>
<properties>
<property name="openjpa.ConnectionDriverName" value="com.mysql.jdbc.Driver" />
<property name="openjpa.ConnectionURL" value="jdbc:mysql://localhost:3306/usermanager?autoReconnect=true" />
<property name="openjpa.ConnectionUserName" value="root" />
<property name="openjpa.ConnectionPassword" value="root" />
</properties>
</persistence-unit>
</persistence>
The error occurs when the following Constructor of my DAO class is executed :
@PersistenceContext(unitName="userManager.model")
private EntityManager em;
private EntityManagerFactory emf;
public UserDAOBean() {
em = emf.createEntityManager();
}
Here's the error I get with OpenJPA not finding MySQL. Of course it is worth mentioning that both the URL and the username/password do work :
<openjpa-2.2.0-r422266:1244990 nonfatal general error> org.apache.openjpa.persistence.PersistenceException: There were errors initializing your configuration: <openjpa-2.2.0-r422266:1244990 fatal user error> org.apache.openjpa.util.UserException: A connection could not be obtained for driver class "com.mysql.jdbc.Driver" and URL "jdbc:mysql://localhost:3306/usermanager?autoReconnect=true". You may have specified an invalid URL.
at org.apache.openjpa.jdbc.schema.DataSourceFactory.newConnectException(DataSourceFactory.java:255)
at org.apache.openjpa.jdbc.schema.DataSourceFactory.newDataSource(DataSourceFactory.java:123)
at org.apache.openjpa.jdbc.conf.JDBCConfigurationImpl.createConnectionFactory(JDBCConfigurationImpl.java:844)
at org.apache.openjpa.jdbc.conf.JDBCConfigurationImpl.getConnectionFactory(JDBCConfigurationImpl.java:732)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.openjpa.lib.conf.ConfigurationImpl.instantiateAll(ConfigurationImpl.java:295)
at org.apache.openjpa.conf.OpenJPAConfigurationImpl.instantiateAll(OpenJPAConfigurationImpl.java:1671)
at org.apache.openjpa.kernel.AbstractBrokerFactory.makeReadOnly(AbstractBrokerFactory.java:646)
at org.apache.openjpa.kernel.AbstractBrokerFactory.newBroker(AbstractBrokerFactory.java:203)
at org.apache.openjpa.kernel.DelegatingBrokerFactory.newBroker(DelegatingBrokerFactory.java:156)
at org.apache.openjpa.persistence.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:227)
at org.apache.openjpa.persistence.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:154)
at org.apache.openjpa.persistence.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:60)
at org.apache.aries.jpa.container.impl.CountingEntityManagerFactory.createEntityManager(CountingEntityManagerFactory.java:64)
at javax.persistence.EntityManagerFactory$$Proxy.createEntityManager(Unknown Source)
I've cut the exception (it keeps going on and on) until this point :
Caused by: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver not found by org.apache.openjpa [12]
at org.apache.felix.framework.BundleWiringImpl.findClassOrResourceByDelegation(BundleWiringImpl.java:1460)
at org.apache.felix.framework.BundleWiringImpl.access$400(BundleWiringImpl.java:72)
at org.apache.felix.framework.BundleWiringImpl$BundleClassLoader.loadClass(BundleWiringImpl.java:1843)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:169)
at org.apache.openjpa.jdbc.schema.DataSourceFactory.newDataSource(DataSourceFactory.java:85)
... 108 more
PS: I couldn't post the links to Aries, OpenJPA or EclipseLink because of the spam restriction, sorry :/