[news.eclipse.newcomer] Re: JPA/EclipseLink 1.0.2 J2SE Project: emf.crea

[Ed Merks <Ed.Merks@xxxxxxxxx>]

Andi,

You'd be better to ask the author directly, I see there's a link for 
that, or to use the EclipseLink newsgroup, which I've added to the "to" 
list of the reply.


Andi wrote:
> I followed some tutorials as e.g. 
> http://www.vogella.de/articles/JavaPersistenceAPI/article.html to 
> setup a Java/JPA project.
>
> I am using a MySQL 5  database together with the MySQLConnector v5.0.4 
> and EclipseLink 1.0.2.
>
> I defined a set of entities. Automatic creation of DDL in the database 
> works. I successfully create some entries in the tables 
> programatically, starting with a JUnit4 Test.
>
> The problem is, that everytime I create a new entity manager all 
> mapped tables are truncated. Thus, every query on a new entity manager 
> returns an empty result.
>
> The test case:
>  @Before
>  public void setUp() throws Exception {
>    emf = Persistence.createEntityManagerFactory("TestJPA");
>  }
>
>  @Test
>  public void doNothing() {
>    emf.createEntityManager().close();
>  }
>
>  @After
>  public void tearDown() {
>    emf.close();
>  }
>
> results in an empty database.
>
> I am afraid, I have some kind of fundamental misunderstanding. The 
> vogella tutorial and all others that I have found do a setup (@Before) 
> that create all queried data in advance, but do not explain why. How 
> can I read peristed data?
>
> This is my persistence.xml:
> <?xml version="1.0" encoding="UTF-8"?>
> <persistence version="1.0" 
> xmlns="http://java.sun.com/xml/ns/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_1_0.xsd";>
>  <persistence-unit name="TestJPA" transaction-type="RESOURCE_LOCAL">
>    <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
>    <class>model.Family</class>
>    <class>model.Job</class>
>    <class>model.Person</class>
>    <class>model.OfficeJob</class>
>    <class>model.OutdoorJob</class>
>    <class>model.Animal</class>
>    <properties>
>      <property name="eclipselink.jdbc.url" 
> value="jdbc:mysql://localhost:3306/test01"/>
>      <property name="eclipselink.jdbc.user" value="root"/>
>      <property name="eclipselink.jdbc.password" value=""/>
>      <property name="eclipselink.jdbc.driver" 
> value="com.mysql.jdbc.Driver"/>
>      <property name="eclipselink.ddl-generation" 
> value="drop-and-create-tables" />
>      <property name="eclipselink.ddl-generation.output-mode" 
> value="database" />
>      <property name="eclipselink.target-database" value="MySQL4"/>
>  </properties>
> </persistence-unit>
> </persistence>
>
>
> Thank you for your help in advance,
>
> Andi