EclipseLink does not work on Netbeans, is this normal?

问题

It'll be weeks that I'm stuck with EclipseLink. I can not persist an object in my database. I use netbeans 7.3. I encountered this problem when I started designing a web application. What follows is the approach I have adopted. It may be that I do without me realize a mistake.

After that netbeans has finished generating the project files I configured the jndi. Then I converted automatically with netbeans, the database tables in entity object. here is the link

then, from these classes, I created their JPAController . (Always automatically with netbeans)

and finally, as a test, I just instantiate the description of "Outils" and leave the fields empty id. Since the latter automatically increment in the database, if the persistence is done well, I should have an id when I appear with out the console.

<body>
    <h1>Hello World!</h1>
    <%
       Outils o = new Outils();
       o.setDesignation("hammers");

       EntityManagerFactory emf = Persistence.createEntityManagerFactory("Test_EclipseLinkPU");
       UserTransaction utx = (UserTransaction) new InitialContext().lookup("java:comp/UserTransaction");

       OutilsJpaController o_ctrl = new OutilsJpaController(utx, emf);
       o_ctrl.create(o);

       out.println("this is the id of hammer " + o.toString());
    %>
</body>

and I get as result: Outils[ id=null ].

I have no error or on glassfish even less about the debugger.

Ps : Here are the persistence.xml file

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" 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_2_0.xsd">
    <persistence-unit name="Test_EclipseLinkPU" transaction-type="JTA">
        <jta-data-source>test_data_source</jta-data-source>
        <exclude-unlisted-classes>false</exclude-unlisted-classes>
        <properties/>
    </persistence-unit>
</persistence>

Thank you for your future is in your answers and listening for any additional information.

回答1:

(Not really an answer but I couldn't show this in a comment) To increase logging your persistence.xml should look like this:

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" 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_2_0.xsd">
    <persistence-unit name="Test_EclipseLinkPU" transaction-type="JTA">
        <jta-data-source>test_data_source</jta-data-source>
        <exclude-unlisted-classes>false</exclude-unlisted-classes>
        <properties>
            <property name="eclipselink.logging.level" value="FINE"/>
            <property name="eclipselink.logging.level.sql" value="FINE"/>
            <property name="eclipselink.logging.parameters" value="true"/>
        </properties>
    </persistence-unit>
</persistence>

回答2:

You need to commit or flush the transaction before anything will be written to the database. If you are using IDENTITY sequencing (I strongly recommend not using IDENTITY, use TABLE or SEQUENCE if db supports it), then the Id cannot be allocated until the insert occurs, so a persist() will not assign the Id (as it does for TABLE and SEQUENCE).

What does your create() method do? How is your Id mapped?

来源：https://stackoverflow.com/questions/16640785/eclipselink-does-not-work-on-netbeans-is-this-normal

标签

jpa

eclipselink

java-ee-6

jta