Re: vectors an synchronizing....

From:
Robert Klemme <shortcutter@googlemail.com>
Newsgroups:
comp.lang.java.programmer
Date:
Tue, 21 Nov 2006 17:20:42 +0100
Message-ID:
<4sgnaoFv5qjqU1@mid.individual.net>
On 21.11.2006 17:06, nullstring wrote:

Hello together (at such a sunny day:)


It's dark here.

I have a question about multithreading!
I want to make a variable count of threads using an (self-implemented)
dbhander-class.
But I don't want to work with 'synchronized', because of the
performance...


What do you mean by that? You need to use synchronize one way or
another if you want to share a resource thread safe (leaving out
volatile etc.). And the performance penalty is negligible - unless you
hold the lock for the complete course of action.

So, when I add a new jdbc-connection in a vector for every new thread,
and all threads work with its own connection, but in the same vector!
Do I have problems with synchronizing?


All Vector methods are synchronized. I don't see how that should create
a problem. But then again it is not very clear from what you write what
you want to do. Is your Vector some form of connection pool? If so,
there are plenty implementations out there - even free ones. And they
have all the whistles and bells...

If I work with the same connection from different threads, YES! (<- I
think)
But only with the same vector????


You cannot use a JDBC connection from multiple threads /at the same time/.

Regards

    robert

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