org.opendaylight.yangtools.objcache

Interface ObjectCache

All Known Implementing Classes:

AbstractObjectCache, NoopObjectCache

public interface ObjectCache

A cache of objects. Caches are useful for reducing memory overhead stemming from multiple copies of identical objects -- by putting a cache in the instantiation path, one can expend some memory on indexes and spend some CPU cycles on walking the index to potentially end up with a reused object. Note that the cached objects should really be semantically Immutable. This interface does not enforce that interface contract simply because there are third-party objects which fulfill this contract.

Method Summary

Methods

Modifier and Type	Method and Description
<B extends ProductAwareBuilder<P>,P> P	getProduct(B builder) Get a reference to an object equal to the product of a builder.
<T> T	getReference(T object) Get a reference for an object which is equal to specified object.

Method Detail

getReference

<T> T getReference(@Nullable
                 T object)

Get a reference for an object which is equal to specified object. The cache is free return either a cached instance, or retain the object and return it back.

Type Parameters:

T - object type

Parameters:

object - Requested object, may be null

Returns:

Reference to an object which is equal to the one passed in. If @object was @null, this method returns @null.

getProduct

<B extends ProductAwareBuilder<P>,P> P getProduct(@Nonnull
                                                B builder)

Get a reference to an object equal to the product of a builder. The builder is expected to remain constant while this method executes. Unlike getReference(Object), this method has the potential of completely eliding the product instantiation.

Type Parameters:

P - produced object type

B - builder type

Parameters:

builder - Builder instance, may not be null

Returns:

Result of builder's toInstance() product, or an equal object.