io.smallrye.mutiny.groups

Class MultiCollect<T>

java.lang.Object

io.smallrye.mutiny.groups.MultiCollect<T>

public class MultiCollect<T>
extends Object

Constructor Summary

Constructors

Constructor and Description
MultiCollect(Multi<T> upstream)

Method Summary

Modifier and Type	Method and Description
Uni<List<T>>	asList() Creates a Uni emitting an item containing all elements emitted by this Multi into a List.
<K> Uni<Map<K,T>>	asMap(Function<? super T,? extends K> keyMapper) Produces an Uni emitting a Map of key -> item for each item emitted by this Multi.
<K,V> Uni<Map<K,V>>	asMap(Function<? super T,? extends K> keyMapper, Function<? super T,? extends V> valueMapper) Produces an Uni emitting a Map of key -> mapped item for each item emitted by this Multi.
<K> Uni<Map<K,Collection<T>>>	asMultiMap(Function<? super T,? extends K> keyMapper) Produces an Uni emitting a Map of key -> Collection of items for each item emitted by this Multi.
<K,V> Uni<Map<K,Collection<V>>>	asMultiMap(Function<? super T,? extends K> keyMapper, Function<? super T,? extends V> valueMapper) Produces an Uni emitting a Map of key -> Collection of mapped values for each item emitted by this Multi.
Uni<T>	first() Creates a Uni receiving the first item emitted by the upstream Multi.
<X> Uni<X>	in(Supplier<X> supplier, BiConsumer<X,T> accumulator) Produces a new Uni emitting a container with all items emitted by this Multi.
Uni<T>	last() Creates a Uni receiving the last item emitted by the upstream Multi.
<X,A> Uni<X>	with(Collector<? super T,A,? extends X> collector) Creates a Uni emitting an item with the object computed by the given Collector.

Methods inherited from class java.lang.Object

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

Constructor Detail

MultiCollect

public MultiCollect(Multi<T> upstream)

Method Detail

first

public Uni<T> first()

Creates a Uni receiving the first item emitted by the upstream Multi. If the Multi is empty, the produced Uni fires null as item when the Multi emits the completion event. If the Multi emits a failure before having emitted an item, the produced Uni propagates the failure.

Returns:

the produced uni

last

public Uni<T> last()

Creates a Uni receiving the last item emitted by the upstream Multi. The last item is item fired just before the completion event.

If the Multi is empty, the produced Uni fires null as item when the Multi emits the completion event. If the Multi emits a failure, the produced Uni propagates the failure.

Returns:

the produced uni

asList

public Uni<List<T>> asList()

Creates a Uni emitting an item containing all elements emitted by this Multi into a List. The produced Uni emits its item when this Multi completes.

Returns:

the Uni emitting the list of items from this Multi.

with

public <X,A> Uni<X> with(Collector<? super T,A,? extends X> collector)

Creates a Uni emitting an item with the object computed by the given Collector. The collector behaves the same way as on a Java stream.

Type Parameters:

A - the accumulation type

X - the item type

Parameters:

collector - the Collector, must not be null

Returns:

a Uni emitted the collected object as item, when the Multi completes

in

public <X> Uni<X> in(Supplier<X> supplier,
                     BiConsumer<X,T> accumulator)

Produces a new Uni emitting a container with all items emitted by this Multi.

It produces the container instance using the passed Supplier (at subscription time) and then call the accumulator bi-consumer for each item emitted by the Multi.

The collected item will be emitted when this Multi fires the completion event.

If the Multi propagates a failure, the produces Uni propagates the same failure, even if some items have been collected. If the Multi is empty, the supplied container is returned empty

Type Parameters:

X - the type of the container produced by the supplier.

Parameters:

supplier - the supplier of the container instance, called at Subscription time. Must not be null. Must not produce null

accumulator - a consumer called on every item with the container instance and the item. It should add the item into the container. Must not be null

Returns:

a Uni emitting the collected container as item when this Multi completes

asMap

public <K> Uni<Map<K,T>> asMap(Function<? super T,? extends K> keyMapper)

Produces an Uni emitting a Map of key -> item for each item emitted by this Multi. The collected map is emitted by the produced Uni when the Multi fires the completion event.

The key is extracted from each item by applying the keyMapper function. In case of conflict, the associated value will be the most recently emitted item.

Type Parameters:

K - the type of the key extracted from each item emitted by this Multi

Parameters:

keyMapper - a Function to map item to a key for the Map. Must not be null, must not produce null

Returns:

a Uni emitting an item with the collected Map. The uni emits the item when this Multi completes

asMap

public <K,V> Uni<Map<K,V>> asMap(Function<? super T,? extends K> keyMapper,
                                 Function<? super T,? extends V> valueMapper)

Produces an Uni emitting a Map of key -> mapped item for each item emitted by this Multi. The collected map is emitted by the produced Uni when the Multi fires the completion event.

The key is extracted from each item by applying the keyMapper function. In case of conflict, the associated value will be the most recently emitted item. The value is computed by applying the valueMapper function.

Type Parameters:

K - the type of the key extracted from each item emitted by this Multi

V - the type of the value extracted from each item emitted by this Multi

Parameters:

keyMapper - a Function to map item to a key for the Map. Must not be null, must not produce null

valueMapper - a Function to map item to a value for the Map. Must not be null, must not produce null

Returns:

a Uni emitting an item with the collected Map. The uni emits the item when this Multi completes

asMultiMap

public <K,V> Uni<Map<K,Collection<V>>> asMultiMap(Function<? super T,? extends K> keyMapper,
                                                  Function<? super T,? extends V> valueMapper)

Produces an Uni emitting a Map of key -> Collection of mapped values for each item emitted by this Multi. The collected map is emitted by the produced Uni when the Multi fires the completion event.

The key is extracted from each item by applying the keyMapper function. The value is a collection containing all the values mapped to the specific key. The value is computed by applying the valueMapper function.

Type Parameters:

K - the type of the key extracted from each item emitted by this Multi

V - the type of the value extracted from each item emitted by this Multi

Parameters:

keyMapper - a Function to map item to a key for the Map. Must not be null, must not produce null

valueMapper - a Function to map item to a value for the Map. Must not be null, must not produce null

Returns:

a Uni emitting an item with the collected Map. The uni emits the item when this Multi completes

asMultiMap

public <K> Uni<Map<K,Collection<T>>> asMultiMap(Function<? super T,? extends K> keyMapper)

Produces an Uni emitting a Map of key -> Collection of items for each item emitted by this Multi. The collected map is emitted by the produced Uni when the Multi fires the completion event.

The key is extracted from each item by applying the keyMapper function. The value is a collection containing all the items emitted associated to the specific key.

Type Parameters:

K - the type of the key extracted from each item emitted by this Multi

Parameters:

keyMapper - a Function to map item to a key for the Map.Must not be null, must not produce null

Returns:

a Uni emitting an item with the collected Map. The uni emits the item when this Multi completes