Have you read this? http://tapestry.apache.org/integrating-with-jpa.html
You should @Inject EntityManager, if you do things right you won't have to create EntityManager instances yourself. Also, saying that you have NPE, it would be nice if you provide us a stacktrace. On Fri, Oct 11, 2013 at 2:48 PM, Andreas Ernst <a...@ae-online.de> wrote: > Hi, > > i am playing with JPA, but there is no useful information about that. A > simple example to display a database table. > > The entities class is in the right package entities. I did not added > something to the AppModule class. The persistence.xml exists. > > Customer.tml > > <html t:type="layout" title="Customer" > > xmlns:t="http://tapestry.**apache.org/schema/tapestry_5_**3.xsd<http://tapestry.apache.org/schema/tapestry_5_3.xsd> > " > xmlns:p="tapestry:parameter"> > <table t:type="grid" source="customers"/> > </html> > > > Customers.class > > public class Customers { > > @Property > private Customer customer; > private EntityManagerFactory factory; > private EntityManager entityManager; > @Inject > private Logger logger; > @Inject > private BeanModelSource beanModelSource; > @Inject > private Messages messages; > > @Log > public List<Customers> getCustomers() { > factory = Persistence.**createEntityManagerFactory("** > de.aeits_TapestryWeb_war_1.0-**SNAPSHOTPU"); > entityManager = factory.createEntityManager(); > return entityManager.**createNamedQuery("Customer.** > findAll").getResultList(); > } > } > > > What about the DAO and DAOImpl there are no informations how to use this > classes with a simple query page. > > In all docus i found only > 'entityManager.**createNamedQuery("Customer.**findAll").getResultList();' > is needed, but i get a null pointer expection. > > Thanks > Andreas > -- > ae | Andreas Ernst | IT Spektrum > Postfach 5, 65612 Beselich > Schupbacher Str. 32, 65614 Beselich, Germany > Tel: +49-6484-91002 Fax: +49-6484-91003 > a...@ae-online.de | www.ae-online.de > www.tachyon-online.de > > ------------------------------**------------------------------**--------- > To unsubscribe, e-mail: > users-unsubscribe@tapestry.**apache.org<users-unsubscr...@tapestry.apache.org> > For additional commands, e-mail: users-h...@tapestry.apache.org > > -- Dmitry Gusev AnjLab Team http://anjlab.com
