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session.flush(); gives null

sam liya
Ranch Hand

Joined: Nov 25, 2008
Posts: 1208
this is my hibernate.cfg.xml code



this is my Contact,java code


this is my contact.hbm.xml code


this is my test class

in the test class session.flush(); gives null
here is the error
Rahul Babbar
Ranch Hand

Joined: Jun 28, 2008
Posts: 210
Hi,

Quite a few things..

1. Create a Transaction and save your entity inside that transaction.
2. Check to see if you got any exception while building the session factory...i.e. any exception on the console before this error.

it is possible that the creation of your sessionFactory and session failed(ie and error in line 21), and your session is null, hence giving a null pointer...


Rahul Babbar
sam liya
Ranch Hand

Joined: Nov 25, 2008
Posts: 1208
but if i comment the flush and close it gives this
sam liya
Ranch Hand

Joined: Nov 25, 2008
Posts: 1208
anyway how to save this in a transaction?
sam liya
Ranch Hand

Joined: Nov 25, 2008
Posts: 1208
i only add the hibernate3.jar and mysql-connector-java-3.1.6-bin.jar.ithink it is enough.
Rahul Babbar
Ranch Hand

Joined: Jun 28, 2008
Posts: 210
aruna sameera wrote:but if i comment the flush and close it gives this

Add the commons-logging.jar to your application classpath.

You need to save the entities in a Transaction like

Transaction tx = session.beginTransaction();
// populate and save your entity.
tx.commit();
// if some exception occurs, check if the transaction is Active, if it is, do a tx.rollback();


Please do a 'google' for some hibernate tutorials, go through them for proper understanding.
sam liya
Ranch Hand

Joined: Nov 25, 2008
Posts: 1208
i change my test class to this


then error is
Rahul Babbar
Ranch Hand

Joined: Jun 28, 2008
Posts: 210
aruna sameera wrote:i change my test class to this


clearly it says that your hibernate.cfg.xml file is not found. Do you have such a file. If yes, where is it?
Please go through some simple hibernate tutorial on the net..
Cameron Wallace McKenzie
author and cow tipper
Saloon Keeper

Joined: Aug 26, 2006
Posts: 4968
    
    1

Indeed, it looks like it's the location of the hibernate.cfg.xml file that's at issue.

People often put it next to a HibernateUtil class or in a package folder. The root of your source folder should be good enough.

Here's a little tutorial on setting up Hibernate that might be helpful. Just get something simple started and working, and progress from there.

Getting Started with Hibernate


-Cameron McKenzie
 
Consider Paul's rocket mass heater.
 
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