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singleton pattern in java

jayakumar elumalai

Joined: Apr 21, 2003
Posts: 1
I have heard about using patterns in core java.Is it possible?If yes, how?
subhit chauhan
Ranch Hand

Joined: Jun 20, 2002
Posts: 40
patterns are designing stuff.... you can use any types of patterns in any technology.... check this link out
for Java design patterns.....
Dirk Schreckmann

Joined: Dec 10, 2001
Posts: 7023
For example, a Java implementation of the Singleton Pattern might be as follows.

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Stan James
(instanceof Sidekick)
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Joined: Jan 29, 2003
Posts: 8791
As you study singletons, be aware of a pattern once (but no longer) recommended by Sun that has been shown not to work on multi-processor machines and in some cases in multi-threaded apps on a single processor. If you see code like:

Run away! Here is an article on whyDouble-Checked Locking can get you in trouble.

A good question is never answered. It is not a bolt to be tightened into place but a seed to be planted and to bear more seed toward the hope of greening the landscape of the idea. John Ciardi
John Smith
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Joined: Oct 08, 2001
Posts: 2937

The Singleton
Oh Singleton, -- to use or not to use?
The grace of pattern overwhelms me, --
You've been the subject of abuse,
Or so the sheriffs try to tell me
The heat of virtual hot spot machine
Makes my initializers slow and lazy
But the class loaders are really mean,
They make two instances, amazing!
And then the garbage man comes in
To claim the memory unreferenced
And when I call it from the bean
It's doubleton, as if I had no preference!
The call to get an instance comes along,
But gets preempted by someone to blame.
I now have a tripleton, and I am prone
To crashes, errors, tears, and pain.
I agree. Here's the link:
subject: singleton pattern in java
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