Pooling Component adapter

From Ross Mason:

I have implemented a simple component pool which uses a PicoContainer for the pool and is itself picofiable. The pool supports exhausted policies ? Fail, Grow and Block.

This is what it looks like ?

//Creates a default pool of AnotherTouchable

DefaultPicoPool pool = new DefaultPicoPool(AnotherTouchable.class);

There is another constructor that accepts a PicoPoolConfiguration, i.e.

MutablePicoContainer pico = new DefaultPicoContainer();

PicoPoolConfiguration config = new PicoPoolConfiguration(AnotherTouchable.class, ...Other pool parameters);

pico.registerComponentInstance(config);

pico.registerComponentImplementation("myPool", DefaultPicoPool.class);

DefaultPicoPool pool = (DefaultPicoPool) pico.getComponentInstance("myPool");

To obtain objects call ?

Object borrowed = pool.borrowComponent();

And to return ?

Pool.returnComponent(borrowed);

I?ve included the source with test cases. I was also going to implement a keyed Pool version, but wanted to check I was on the right track.

Also, I started playing with a PicoPoolComponentAdapter that would provide pooling transparently i.e.

MutablePicoContainer pico = new DefaultPicoContainer(new PicoPoolComponentAdapterFactory());

pico.registerComponentImplementation(AnotherTouchable.class);

AnotherTouchable component = (AnotherTouchable)pico.getComponentInstance(AnotherTouchable.class);

component.wasTouched();

AnotherTouchable component2 = (AnotherTouchable)pico.getComponentInstance(AnotherTouchable.class);

assertTrue(!component2.isTouched());

I couldn?t think of a clean way of returning the object to the pool once it had been borrowed. Any ideas??

Cheers,

Ross

Ps this uses Zohar?s NonCachingComponentAdapter, so you?ll need that code to run it.

>>this uses Zohar?s NonCachingComponentAdapter

Note that in the last patch uploaded to PICO-55, NonCachingComponentAdapter has been renamed :
BasicComponentAdapter.

Yes, and it's actually been renamed again. It's now "TransientComponentAdapter".

Is this more of a Pico-component than an actual part of the Pico-core? Move to PicoExtras?

Agreed, pooling is definitely an extra.

Added to PicoExtras

I have started to look at this.

It looks very interesting, but also quite complicated with the threading stuff.

Why are threads needed?