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Hi Joshua. Interesting article.
I noted that an earlier poster tried this in Derby and couldn't get first to work. I also got this working in Derby but it took a bit of jumping through hoops so I'm going to detail the steps I took in case it helps someone else. :D
But before I do - it may be worth noting that rather than changing Person.java as I and the previous poster did, the 'zen' of EE 5 is to probably change the column it maps to via the Annotation (though there is a certain elegance to letting the db pick up and run with a default column name as well...)
So here's what I did:
- Type in classes as per example.
- Fiddle the persistence.xml
- I put the Toplink essentials jar in my classpath.
- Got a strange exception.
- Suspected something was wrong with my persistence.xml. Moved it out of my project directory entirely.
- Still got same error.
- Read the article more carefully. Ahha! It has to go in the META-INF directory. *blushes*.
- Run it again, this time I get a bunch of output about how it is going to do the mapping... looking good so far... and I get a whopping big error which boils down to:
Configuration error. Class [org.apache.derby.jdbc.ClientDriver] not found.
- Oops. Try to find this class on my system. No dice.
- Go and download the Derby zip from the apache site. Unpack the zip and slap the jars which start with Derby (as prime suspects) on my classpath.
- Great, we have fluffy dice.
- Oh wait, what is this? Derby is not running? Umm... fire up Netbeans and run it through the runtime console (not sure if this is cheating).
- Fantastic, now it complains about FIRST in the SQL statement. No problem, fix the class... and we are good to go, tables and data show up in the Netbeans inspector.
*phew*
NB: much fiddling with the persistence.xml ommitted for the sake of brevity.
For reference, here is the persistence.xml file I ended up using:
(oh darn, there is no preview... this is gonna look bad)
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="1.0" xmlns="http://java.sun.com/xml/ns/persistence">
<persistence-unit name="sample" transaction-type="RESOURCE_LOCAL">
<provider>oracle.toplink.essentials.ejb.cmp3.EntityManagerFactoryProvider</provider>
<class>addressbook.Person</class>
<properties>
<property name="toplink.jdbc.user" value="****"/>
<property name="toplink.jdbc.password" value="****"/>
<property name="toplink.jdbc.url" value="jdbc:derby://localhost:1527/sample"/>
<property name="toplink.jdbc.driver" value="org.apache.derby.jdbc.ClientDriver"/>
<property name="toplink.ddl-generation" value="create-tables"/>
</properties>
</persistence-unit>
</persistence>
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