Singleton class issue

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Singleton class issue

Singleton class issue

2004-11-17 - By Binildas

Back

Reply: 1 2 3 4 5

Bill,

The simplest (and preferred) method is to design the methods inside your
singleton class as idempotent. This can be achieved by not using any
writable, instance fields in your singleton class. If so, even if the
methods are executed concurrently by multiple threads (either in a
single CPU or multiple CPU m/c), each thread will be executing in its
"separate, local stack memory" only.

Regards

Binildas
Senior Technical Architect

http://www.infosys.com <http://www.infosys.com/>

-- --Original Message-- --
From: A mailing list for Java(tm) 2 Platform, Enterprise Edition
[mailto:J2EE-INTEREST@(protected)] On Behalf Of bin cai
Sent: Thursday, November 18, 2004 7:41 AM
To: J2EE-INTEREST@(protected)
Subject: Singleton class issue

Hello,

I am developing web application based on j2ee technology:jsp, java bean
and jdbc.

I ceated a singleton class called "JdbcController.java" that takes the
responsibility to establishing connection to DB and works fine. But my
concern is :since this is multi-thread application. every thread will
invoke JDBCController class . i am wondering if this will result in
concurrent issue becase every thread will compete to use this class to
get connection to DB.

one alternative is :i don't use singleton pattern. when every thread
needs to get access to DB, it will ceate new instance of JDBCControoler
object. but it will use lot of memory although JVM has garbage
collection mechanism.

So which way is better according to you guys' experience. Please let me
know.

Thanks

bill

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Bill,

 

The simplest (and preferred) method is to
design the methods inside your singleton class as idempotent. This can be
achieved
by not using any writable, instance fields in your singleton class. If so, even
if the methods are executed concurrently by multiple threads (either in a
single CPU or multiple CPU m/c), each thread will be executing in its &#8220
;separate,
local stack memory” only.

 

Regards 

 

Binildas 
Senior Technical Architect

<a href="http://www.infosys.com/">http://www.infosys.com</a>


 

-- --Original Message-- -- 
From: A mailing list for Java(tm)
2 Platform, Enterprise Edition [mailto:J2EE-INTEREST@(protected)] On Behalf Of bin cai 
Sent: Thursday, November 18, 2004
7:41 AM 
To: J2EE-INTEREST@(protected) 
Subject: Singleton class issue

 

<div>

Hello,

</div>

<div>

I am developing web application based on j2ee
technology:jsp, java bean and jdbc.

</div>

<div>

I ceated a singleton class called
"JdbcController.java" that takes the responsibility to&nbsp
;establishing  
connection to DB and works fine. But my concern is :since this is
multi-thread application. every thread will
invoke JDBCController class . i am wondering if this will result
in concurrent issue becase every thread will compete to use this class to get
connection to DB.

</div>

<div>

one alternative is :i don't use singleton pattern.
when every thread needs to get access to DB, it will ceate new instance of
JDBCControoler object. but it will use lot of memory although JVM has
garbage collection mechanism.

</div>

<div>

So which way is better according to you guys'
experience. Please let me know.

</div>

<div>

Thanks

</div>

<div>

bill  

</div>

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Tired of spam? Yahoo! Mail has the best spam protection around 
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