io.micronaut.context

Interface BeanProvider<T>

Type Parameters:

T - The type

All Superinterfaces:

java.lang.Iterable<T>

public interface BeanProvider<T>
extends java.lang.Iterable<T>

A provider contract.

Since:

2.4.0

Author:

James Kleeh, graemerocher

Method Summary

Modifier and Type	Method and Description
static <T1> Argument<BeanProvider<T1>>	argumentOf(java.lang.Class<T1> type) Create an argument for the given type to aid with bean provider lookup.
T	get()
default T	get(Qualifier<T> qualifier)
default void	ifPresent(java.util.function.Consumer<T> consumer) Executes the given logic if the bean is present.
default void	ifResolvable(java.util.function.Consumer<T> consumer) Executes the given logic if the bean is resolvable.
default boolean	isPresent() Determines if there is a bean that matches the required type and qualifiers.
default boolean	isResolvable() Is the bean resolvable using the get() or ifPresent(Consumer) methods.
default boolean	isUnique() Determines if more than one bean matches the specified type and qualifiers.
default java.util.Iterator<T>	iterator()
default T	orElse(T alternative) Allows selecting an alternative bean if the backing bean is not present.
default java.util.stream.Stream<T>	stream() When called, provides back a Stream of the beans available in this provider.

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Method Detail

get

@NonNull
T get()

Returns:

A fully-constructed and injected instance of T.

get

@NonNull
default T get(@Nullable
                       Qualifier<T> qualifier)

Parameters:

qualifier - The qualifier to use.

Returns:

A fully-constructed and injected instance of T.

Since:

3.0.0

iterator

@NonNull
default java.util.Iterator<T> iterator()

Specified by:

iterator in interface java.lang.Iterable<T>

stream

default java.util.stream.Stream<T> stream()

When called, provides back a Stream of the beans available in this provider. If no beans are found, it returns an empty stream.

Returns:

a Stream representing the beans associated with this BeanProvider object

Since:

3.0.0

isUnique

default boolean isUnique()

Determines if more than one bean matches the specified type and qualifiers.

>

Returns:

true if only one bean matches.

Since:

3.0.0

isPresent

default boolean isPresent()

Determines if there is a bean that matches the required type and qualifiers.

Returns:

true if at least one bean matches.

Since:

3.0.0

isResolvable

default boolean isResolvable()

Is the bean resolvable using the get() or ifPresent(Consumer) methods.

A bean is said to be resolvable when it is both unique (see isUnique()) and present (see isPresent())

Returns:

True if the bean is resolvable

Since:

3.0.0

ifPresent

default void ifPresent(@NonNull
                       java.util.function.Consumer<T> consumer)

Executes the given logic if the bean is present. Executes get() to obtain the bean which may result in a NonUniqueBeanException if the bean is not unique.

Parameters:

consumer - the consumer

Throws:

NonUniqueBeanException - if the bean is not unique

Since:

3.0.0

See Also:

isPresent()

ifResolvable

default void ifResolvable(@NonNull
                          java.util.function.Consumer<T> consumer)

Executes the given logic if the bean is resolvable. See isResolvable().

Parameters:

consumer - the consumer

Since:

3.0.0

See Also:

isResolvable()

argumentOf

@NonNull
static <T1> Argument<BeanProvider<T1>> argumentOf(@NonNull
                                                           java.lang.Class<T1> type)

Create an argument for the given type to aid with bean provider lookup.

Type Parameters:

T1 - The generic type

Parameters:

type - The type

Returns:

3.0.0

orElse

@Nullable
default T orElse(@Nullable
                           T alternative)

Allows selecting an alternative bean if the backing bean is not present.

Parameters:

alternative - The alternative, can be null

Returns:

The bean if present or else the supplied alternative

Since:

3.0.2