I confused about autocommit set in hibernate source code

jian_xiao · **Posted:** Sat Mar 27, 2004 8:47 am

I confused about autocommit set in hibernate source code:

in DatasourceConnectionProvider.java

Quote:

public Connection getConnection() {
...
return ds.getConnection();
}

but in DriverManagerConnectionProvider.java

Quote:

public Connection getConnection(){

...
if ( pooled.getAutoCommit() ) pooled.setAutoCommit(false);
return pooled;
}

So there are errors in a transaction when using app server datasource in hibernate.cfg.xml and it is ok when using connections properties.The file I used was like:

Quote:

<hibernate-configuration>
<session-factory name="java:/hibernate/SessionFactory">

<property name="connection.datasource">java:/YWAFDS
</property>
<property name="connection.provider_class">net.sf.hibernate.connection.DatasourceConnectionProvider
</property>
<property name="dialect">net.sf.hibernate.dialect.MySQLDialect
</property>


<mapping resource="User.hbm"/>
</session-factory>
</hibernate-configuration>

why?

joib · **Joined:** Wed Mar 03, 2004 9:38 am **Posts:** 70

Perhaps the hibernate team assumed that anyone advanced enough to use a datasource would also be advanced enough to turn autocommit off (thus making it unnecessary to explicitly test for it in the hibernate code)?

Autocommit is useful when working with the command-line SQL tool that comes with your database, but for building actual applications it's a fundamentally broken approach, IMHO.

christian · **Posted:** Sat Mar 27, 2004 3:10 pm

An application server should not give you a JDBC connection with autocommit set to on, if you think about it.

jian_xiao · **Posted:** Sun Mar 28, 2004 6:03 am

Hibernate can configured to use JDBC transaction or JTA transaction,but
the two way are inconsisent. Consider the following codes:
in a JDBC transaction:

Code:

Session session = sf.openSession();
Transaction tx = session.beginTransactioin();
...
session.flush();
tx.commit();
session.close();

but in a JTA transaction:

Code:

javax.transaction.UserTransaction tx = new InitialContext().lookup("javax.transaction.UserTransaction");
Session s1 = sf.openSession();
...
s1.flush();
s1.close();
...
Session s2 = sf.openSession();
...
s2.flush();
s2.close();

tx.commit();

So I must choose a type of transaction hardcoded in my program and change between them in the future are become impossible,is it?

joib · **Joined:** Wed Mar 03, 2004 9:38 am **Posts:** 70

christian wrote:

An application server should not give you a JDBC connection with autocommit set to on, if you think about it.

I don't know if you're answering to me or to jian_xiao, but that was exactly the point I was trying to make. ;-)

joib · **Joined:** Wed Mar 03, 2004 9:38 am **Posts:** 70

jian_xiao wrote:

Hibernate can configured to use JDBC transaction or JTA transaction,but
the two way are inconsisent. Consider the following codes:
in a JDBC transaction:

Sorry, I don't understand your point. AFAIK, the hibernate transaction API is a wrapper around either the JDBC transaction API or JTA, depending on how you configure it. So if you configure hibernate to use JTA transactions, you can use the Hibernate transaction API and behind the scene JTA is used.

A few other points:

1. When using the Hibernate API, committing a transaction automatically flushes the session, so there is no need to explicitly call flush().

2. You second example seems to use the session-per-operation antipattern. Unless you have _very_ good reasons to do otherwise, I think it would be a good idea to follow the guidelines at
http://www.hibernate.org/168.html

3. Using declarative transactions, supported e.g. by the spring framework, you would avoid a lot of boring and repetetive code.

Quote:

So I must choose a type of transaction hardcoded in my program and change between them in the future are become impossible,is it?

Hey, as your very own signature says:

Quote:

Nothing is impossible to a willing heart

;-)

jian_xiao · **Posted:** Mon Mar 29, 2004 9:31 pm

Thank you,joib! I have read the articles you recommended,and these ideas really benefit me greatly!

KaKaXi · **Posted:** Tue Mar 30, 2004 12:12 am

jian_xiao wrote:

Thank you,joib! I have read the articles you recommended,and these ideas really benefit me greatly!

hi Xiao Jian

come here
http://forum.javaeye.com

some great guys talking about hibernate in chinese^_^

btw:I dont think JTA surport in hibernate is perfect for your rigorous APP