org.grouplens.grapht

Class Instantiators

java.lang.Object

org.grouplens.grapht.Instantiators

public final class Instantiators
extends Object

Utilities and methods for building and working with Instantiators.

Since:

0.9

Author:

GroupLens Research

Method Summary

Modifier and Type	Method and Description
static Instantiator	memoize(Instantiator instantiator) Memoize an instantiator.
static Instantiator	ofInstance(Object inst) Create an instantiator that returns an instance.
static Instantiator	ofNull(Class<?> type) Create an instantiator that returns a null value.
static Instantiator	ofProvider(javax.inject.Provider<?> provider) Convert a providerInstantiator to an instantiator.
static Instantiator	ofProviderInstantiator(Instantiator pinst) Flatten an instnatiator of providers into an instantiator of the provided type.
static javax.inject.Provider<?>	toProvider(Instantiator instantiator) Convert an instantiator to a provider.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

ofInstance

public static Instantiator ofInstance(Object inst)

Create an instantiator that returns an instance.

Parameters:

inst - The instance to return (must be non-null).

Returns:

An instantiator that returns inst.

ofNull

public static Instantiator ofNull(Class<?> type)

Create an instantiator that returns a null value.

Parameters:

type - The type of null value to return.

Returns:

An instantiator that returns null.

ofProvider

public static Instantiator ofProvider(javax.inject.Provider<?> provider)

Convert a providerInstantiator to an instantiator. Any exception thrown by the provider - including a runtime exception - is wrapped in an ConstructionException.

Parameters:

provider - The providerInstantiator to wrap.

Returns:

An instantiator wrapping providerInstantiator.

ofProviderInstantiator

public static Instantiator ofProviderInstantiator(Instantiator pinst)

Flatten an instnatiator of providers into an instantiator of the provided type. Any exception thrown by the provider - including a runtime exception - is wrapped in an ConstructionException.

Parameters:

pinst - The providerInstantiator instantiator to wrap.

Returns:

An instantiator wrapping providerInstantiator.

toProvider

public static javax.inject.Provider<?> toProvider(Instantiator instantiator)

Convert an instantiator to a provider.

Parameters:

instantiator - The instantiator to convert.

Returns:

A provider whose Provider.get() method invokes the instantiator.

memoize

public static Instantiator memoize(Instantiator instantiator)

Memoize an instantiator.

Parameters:

instantiator - The instantiator to memoize.

Returns:

An instantiator that memoizes instantiator.