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RE: [eclipselink-users] Eclipselink reconnects to db on each call

Well, I am not closing em or the EMF.  I tried making EMF a static
protected value and now my queries all fail, not sure why that would be.
I do wrap the query in a function like this:

public Query createNamedQuery(String s) throws Exception {
        Query query = null;
        try {
            System.out.println("query is...." + s);
            query = em.createNamedQuery(s);
        catch (Exception e) {
        return query;

The name of the query is coming through but it doesn't seem to be
running the actual SQL I have on the entity objects.

-----Original Message-----
From: eclipselink-users-bounces@xxxxxxxxxxx
[mailto:eclipselink-users-bounces@xxxxxxxxxxx] On Behalf Of Gordon Yorke
Sent: Friday, December 07, 2007 10:42 AM
To: EclipseLink User Discussions
Subject: RE: [eclipselink-users] Eclipselink reconnects to db on each

The symptoms suggest that you are releasing the
EntityManagerFactory(EMF) for garbage collection or actually closing the
EMF.  If there are no active EMFs in your application then EclipseLink
will close out the backing sessions effectively shutting down the
Persistence Service.  This functionality allows for redeployment of your
Try holding a static reference to the EMF you create or make sure that
the EMF is held for the life of your application.

-----Original Message-----
From: eclipselink-users-bounces@xxxxxxxxxxx
[mailto:eclipselink-users-bounces@xxxxxxxxxxx]On Behalf Of Vespa,
Anthony J
Sent: Friday, December 07, 2007 9:37 AM
To: EclipseLink User Discussions
Subject: [eclipselink-users] Eclipselink reconnects to db on each call


I'm having a bit of an issue and wondering if anyone has seen this

I have a persistence.xml with 3 different persistence units as I have
segmented my logic into three different Oracle schema.  Within the Java
code, there are times where I access different persistence units
(depending on the data I need) - now that I am using cache coordination,
performance seems much worse, and part of it seems to be that within 30
seconds or so of a call being executed, the connections to the various
Pus are closed and the connection is logged out.

If I comment out the lines for cache coordination / RMI, things work as
they should - eg it doesn't time out and performance is reasonable.

I did add this property to my persistence.xml just to see if it had any

<property name="eclipselink.jdbc.timeout" value="300000"/>

But it didn't seem to.

To actually get a connection I am calling a getMamanger() function in a
class that looks like this:from some of my business logic:

public class DBManager {

    protected RMICacheCoordinationConfig RMIcc;
    protected EntityManagerFactory emf;
    protected EntityManager em;

     public EntityManager getManager(String s) {
        try {
            if (emf == null) {
                emf = Persistence.createEntityManagerFactory(s);
			RMIcc = new  RMICacheCoordinationConfig();
                em = emf.createEntityManager();
        catch (Exception e) {
        return em;


I have a series of helper wrapper functions that call the different
EntityManager functions (load, remove, etc)

My RMI Caching function is what I got from the eclipselink list last
week - I'm new to RMI so I might have forgotten something:

public class RMICacheCoordinationConfig {

    public void customize(Session session) throws Exception {
            AbstractSession sessionImpl = (AbstractSession) session;

            RemoteCommandManager cm = new
            try {
            } catch (Exception e) {


Thanks for any help!

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