Sagar Kar

My SQL is

with networkids as
(
select s.default_network_id id from store s where s.id=?
union
select nfs.network_id as id from
store s
inner join network_fixed_sched nfs on s.id=nfs.store_id
where s.id=:store1id
union
select nws.network_id as id from
store s
inner join network_weekly_sched nws on s.id=nws.store_id
where s.id=:store1id
)
select count(*) from network_detail nd, networkids ids
where nd.network_id=ids.id
and nd.store_id=store2id

I am unable to convert this to a HQL. But before this SQL is fired I am deleting a row using HQL. I don't want that row to be picked up in this SQL.

15 years ago

Also direct SQL means native SQL.
like
select id,name from EMPLOYEE

15 years ago

Thank you Mark for you prompt reply.
I am using transaction properties

<prop key="hibernate.transaction.factory_class">
org.hibernate.transaction.CMTTransactionFactory
</prop>
<propkey="hibernate.transaction.manager_lookup_class">
org.hibernate.transaction.WebSphereExtendedJTATransactionLookup
</prop>

Also I am using Spring's AOP to demarcate transactions.
From your post what i understand is that mixing hql and sql won't create any problem.

15 years ago

I have a question regarding mixing SQL and HQL in the same transaction.
Consider a table EMPLOYEE.
It has 3 records. I start a transaction. I fire a HQL and delete an Employee record. I fire a direct SQL select on the EMPLOYEE table in the same transaction.
How many records will I get? 2 or 3?
I am not using a second level cache.
Is it okay to mix SQL and HQL in the same transaction?
I am not using any second level cache.

15 years ago

Java Batch Job Design Question

I found one possible solution.
We use IBM's Websphere Application Server 6.0 XD. It has something called a Compute Grid. This can be used to run the jobs and expose these jobs as EJB's or web services.

15 years ago

Java in General

Java Batch Job Design Question

I have around 10 java batch jobs that I run from command line.
All these jobs are a bunch of java classes.

Background:

Our company gets monthly information from different places in form on Microsoft Access Database files.

We have a central oracle database which maintain the relationship between all these data and needs to be updated with the latest data contained in these mdb files.

Now the boss wants a GUI to be able to start and stop and look at the status of the job while it is running.

The jobs take different parameters so the UI should have a way to accept different inputs just like an html form.
We have a shared drive where we drop the mdb files before we run the command jobs.

Any ideas about how to go about it?

Idea 1:

I was thinking of writing a web application.
But few jobs might take as much as 2 hrs to run.
So it may not be a good idea to run them from an appserver.
Holding up appserver threads doesn't seem to be a good idea.

Idea 2:
I have access to all the source files.
Convert the batch jobs to Remote Objects and run them on as remote service thru rmi registry.

But what about the UI? Can I have a web application, running on a appserver like tomcat, which can invoke the rmi objects and then check there status?

Any new ideas? What would be the best way of solving this problem.

Thank you.

15 years ago

Java in General

keytool and self signing certificate

I found the following information from the sun site http://java.sun.com/j2se/1.3/docs/tooldocs/win32/keytool.html#genkeyCmd

Since I am a java guy I am also posting this query in the java forum.

When we use the -genkey argument the keytool "generates a key pair (a public key and associated private key). Wraps the public key into an X.509 v1 self-signed certificate, which is stored as a single-element certificate chain".

When we use the -selfcert argument the keytool "generates an X.509 v1 self-signed certificate, using keystore information including the private key and public key associated with alias".

If -genkey generates a self signed certificate what does -selfcert do?
I can't understand what actually happens between -genkey and -selfcert.
What does self sign mean in both the case?

17 years ago

Java in General

keytool and self signing certificate

I found the following information from the sun site http://java.sun.com/j2se/1.3/docs/tooldocs/win32/keytool.html#genkeyCmd

When we use the -genkey argument the keytool "generates a key pair (a public key and associated private key). Wraps the public key into an X.509 v1 self-signed certificate, which is stored as a single-element certificate chain".

When we use the -selfcert argument the keytool "generates an X.509 v1 self-signed certificate, using keystore information including the private key and public key associated with alias".

If -genkey generates a self signed certificate what does -selfcert do?
I can't understand what actually happens between -genkey and -selfcert.
What does self sign mean in both the case?

17 years ago

Security

It's party time............Cleared with 100%

Contrats !!!
Now can you please reply to the following ....
I had posted the query a few day back and no one is replying....
I don't know whether its a silly question or a difficult one..

Think of the Movie and Trailer example.
Think of it as an one to one bidirectional relationship.
There is a movie M1 and a trailer T1.
M1.getTrailer() will give T1 and T1.getMovie() will give M1.
Now suppose I do something like the following....
M1.setTrailer(null);
After the execution of this statment will T1.getMovie() return null or is it still going to return M1?
[ January 26, 2006: Message edited by: Sagar Kar ]

18 years ago

Entity Relationship

Think of the Movie and Trailer example.
Think of it as an one to one bidirectional relationship.
There is a movie M1 and a trailer T1.
M1.getTrailer() will give T1 and T1.getMovie() will give M1.
Now suppose I do something like the following....
M1.setTrailer(null);
After the execution of this statment will T1.getMovie() return null or is it still going to return M1?

Thanks and regards,
Sagar Kar

18 years ago

Entity Bean

Why does EntityBean interface has an unsetEntityContext() method where as SessionBean interface doesn't have an unsetSessionContext() method. What is so special about the unsetEntityContext() method?

18 years ago

what happens to EJB's after throwing exception to client?

Depends on what kind of exception was thrown:
For an Application Exception(checked exception), the instance is not destroyed
For an Non Application Exception(Runtime Exceptions), the instance is not used anymore and the resources are cleaned up by the container.

For more depth answer please refer to the EJB specs.

18 years ago