🚀 go-pugleaf

Jack Frosch <jackfrosch[NO SPAM]@mail.com> wrote:
> IN their book "Design Patterns" the GoF defines the Singleton pattern's
> intent thus: "To ensure a class has only one instance, and provide a global
> point of access to it."

> For Java implementations, I've seen two implementation variations to achieve
> this:

> 1) Some people code all static methods and data in a class, thus ensuring
> only one "instance" of the class exists in the VM.

> 2) Others use an implementation where the class is defines as normal, but
> with a private constructor.  A single public, static method is provided to
> the single instance of the class that's stored as a private instance
> variable.

> Approach #2 clearly meets the pattern description of the GoF, but I'm
> wondering if there are any uniquely-Java reasons why approach #1 might be
> preferable?

I've used something like #1 to control JNI libraries.
I use #2 to control pseudo-singletons that handle tcp listen sockets.
(There can be only one listener on a port, but I can have multiple listeners 
on separate ports.)

-- 
Joi Ellis (TeamB) 
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