I have an interesting problem with the code below. What happens is that this method finishes execution prior to the database finishing its work. So what ends up happening is that later in my thread of execution i am querying the DB (with a new sesssion) for the newly inserted rows, however, the DB is still working on the deleting of the old ones and inserting of the new rows. And i end up getting a weird mix of data.

The problem i am trying to solve is how to force the following statements to finish execution (including the DB work) before returning control to the primary thread of execution in the VM.

Any ideas would be greatly appreciated.

What's happening is that the SQL for inserting the objects is getting executed at the same time as other parts of the application are retrieving data. Ideally i would like all of the inserts to complete, i.e. the while loop to finish executing, before control is returned to the main thread of execution.

Maybe some more details will help.

At a high level, this what i'm trying to accomplish:



1. Save answers
2. Forward to a new page to view answers


What looks like is happening is that the setUserInterestsAnswers() method, which ultimately ends up calling the session.delete() and session.save() methods from the first post, returns control of execution before the database has finished inserting the data. The reason i know this is that when i look at my server log, there are insert SQL statements from the session.save() method call interspersed with SQL statements that retrieve data for the page that is getting forwarded to.

Now, if you follow the code, you'll see that the session.delete() and session.save() calls are made prior to forwarding to the new page, but in execution, it looks like they are happening in parallel.

Does hibernate spawn threads for inserts that run in parallel with the main execution thread???

// delete existing selections
session.delete("some-query-that-returns-the-objects-i-want-to-delete);
session.flush();
// insert new selections
Iterator answers = myAnswers.iterator();
while(answers.hasNext()) {
Answer answer = (Answer) answers.next();
if(answer != null && !answer.getAnswer().equals("")) {
session.save(answer);
}
}

I am officially a part-time idiot :)

The reason it was querying the table that i was updating was because of the following html tag...

<a href="some.jsp" onclick="submitMyForm();">accept changes</a>

what happened was that when you clicked on the 'accept changes' link, it simultaneously retrieved the jsp to view the answers and submitted the form via struts to update the answers.

solution was to replace the href value with a "#" character so that a new page request is not generated...