Package oracle.dbtools.plugin.api.di

Class DeferredInstanceProvider<T>

java.lang.Object

oracle.dbtools.plugin.api.di.DeferredInstanceProvider<T>

Type Parameters:

T - The type of instance to provide

All Implemented Interfaces:

java.lang.Iterable<T>, java.util.function.Supplier<T>, javax.inject.Provider<T>, InstanceProvider<T>

public class DeferredInstanceProvider<T>
extends java.lang.Object
implements InstanceProvider<T>

InstanceProvider implementation that defers resolving an instance until get(), hasMultiple(), isUnsatisfied(), or iterator() is invoked

Since:

19.3.0

Author:

cdivilly

Method Summary

Modifier and Type	Method	Description
static <T> DeferredInstanceProvider<T>	from(TypeQualifier<T> service, InstanceLocator locator)	Instantiate a DeferredInstanceProvider
T	get()	Retrieve the first available instance
boolean	hasMultiple()	Determines if there is more than one available implementation for the required type and qualifiers
boolean	isUnsatisfied()	Determines if there is no available implementation for the required type and qualifiers.
java.util.Iterator<T>	iterator()	When a service has multiple providers (which can be determined by calling InstanceProvider.isAmbiguous()) this iterator enumerates each of the available providers
TypeQualifier<T>	qualifier()	Identifies the constraints used to select matches
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface oracle.dbtools.plugin.api.di.InstanceProvider

getOrNull, isAmbiguous, isAvailable, isUnavailable, orElse, stream

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Method Detail

get

public T get()

Description copied from interface: InstanceProvider

Retrieve the first available instance

Specified by:

get in interface InstanceProvider<T>

Specified by:

get in interface javax.inject.Provider<T>

Specified by:

get in interface java.util.function.Supplier<T>

Returns:

the first available instance

hasMultiple

public boolean hasMultiple()

Description copied from interface: InstanceProvider

Determines if there is more than one available implementation for the required type and qualifiers

Specified by:

hasMultiple in interface InstanceProvider<T>

Returns:

true if there are multiple providers, false otherwise

isUnsatisfied

public boolean isUnsatisfied()

Description copied from interface: InstanceProvider

Determines if there is no available implementation for the required type and qualifiers. If this method returns true, then calling InstanceProvider.get() will raise a RuntimeException

Specified by:

isUnsatisfied in interface InstanceProvider<T>

Returns:

true if there is no provider, false otherwise

iterator

public java.util.Iterator<T> iterator()

Description copied from interface: InstanceProvider

When a service has multiple providers (which can be determined by calling InstanceProvider.isAmbiguous()) this iterator enumerates each of the available providers

Specified by:

iterator in interface InstanceProvider<T>

Specified by:

iterator in interface java.lang.Iterable<T>

Returns:

The set of available providers

qualifier

public TypeQualifier<T> qualifier()

Description copied from interface: InstanceProvider

Identifies the constraints used to select matches

Specified by:

qualifier in interface InstanceProvider<T>

Returns:

TypeQualifier instance

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

from

public static <T> DeferredInstanceProvider<T> from(TypeQualifier<T> service,
                                                   InstanceLocator locator)

Instantiate a DeferredInstanceProvider

Type Parameters:

T - The type of instance to provide

Parameters:

service - The service that needs to be provided

locator - The locator that can provide the service.

Returns:

DeferredInstanceProvider