JAX-WS based WS using EntityManager to persist data to DB

[C Shinde]

Hello,

I am creating some test WebServices.
This service uses CM Entity Manager, so I have the following line of code:

   @PersistenceContext
    EntityManager em;

Now since this in CM Entity Manager with JTA transaction, I dont need to explicitly use UserTransaction as the Container will manage the transactions.
When I call this WS I get an error like

   javax.persistence.TransactionRequiredException
        at com.sun.enterprise.util.EntityManagerWrapper.doTxRequiredCheck(EntityManagerWrapper.java:236)
        at com.sun.enterprise.util.EntityManagerWrapper.doTransactionScopedTxCheck(EntityManagerWrapper.java:200)
        at com.sun.enterprise.util.EntityManagerWrapper.persist(EntityManagerWrapper.java:426)
 

.

I tried using the UserTransaction and explicitly tried comiting the transaction and it did not give this exception but when I checked the DB there were no records, I have read that I should not be using explicit transactions for CM Entity manager.

Also I am attaching my persistent.xml file

  <?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="OrdernLineItemWSPU" transaction-type="JTA">
    <provider>oracle.toplink.essentials.PersistenceProvider</provider>
    <jta-data-source>jdbc/sample</jta-data-source>
    <exclude-unlisted-classes>false</exclude-unlisted-classes>
    <properties>
    </properties>
  </persistence-unit>
</persistence>
  

My tables are already present.

Any help is appreciated. Thanks in advance.

[C Shinde]

Hello All,

I think I got the answer but partially...

Here the link where I read about the solution :

webpage

But I am not sure why I cannot inject the EntityManager directly into a web application/Service, other than the Syncronization issue?

Here he says that I should use the EntityManagerFactory that is ThreadSafe against the EntityManager, so basically use Application Managed Entity Manager.

Please share your comments.