io.smallrye.mutiny.groups

Class UniOnItem<T>

java.lang.Object

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

public class UniOnItem<T>
extends Object

Constructor Summary

Constructors

Constructor and Description
UniOnItem(Uni<T> upstream)

Method Summary

Modifier and Type	Method and Description
<R> Uni<R>	apply(Function<? super T,? extends R> mapper) Deprecated. use transform(Function)
<O> Uni<O>	castTo(Class<O> target) Produces an Uni emitting an item based on the upstream item but casted to the target class.
UniOnItemDelay<T>	delayIt() Produces a new Uni receiving an item from upstream and delaying the emission on the item event (with the same item).
Uni<T>	failWith(Function<? super T,? extends Throwable> mapper) Produces a new Uni invoking the given function when the current Uni fires an item.
UniOnNotNull<T>	ifNotNull() Adds specific behavior when the observed Uni fies a non-null item.
UniOnNull<T>	ifNull() Adds specific behavior when the observed Uni fires null as item.
UniOnItemIgnore<T>	ignore() Produces a Uni ignoring the item of the current Uni and continuing with either another item, a failure, or another Uni.
Uni<T>	invoke(Consumer<? super T> callback) Produces a new Uni invoking the given callback when the item event is fired.
Uni<T>	invokeUni(Function<? super T,? extends Uni<?>> action) Produces a new Uni invoking the given @{code action} when the item event is received.
<R> Uni<R>	produceCompletionStage(Function<? super T,? extends CompletionStage<? extends R>> mapper) Deprecated. Use transformToUni(Function) and produce the Uni using Uni.createFrom().completionStage(...)
<R> Multi<R>	produceMulti(Function<? super T,? extends org.reactivestreams.Publisher<? extends R>> mapper) Deprecated. Use transformToMulti(Function)
<R> Uni<R>	produceUni(BiConsumer<? super T,UniEmitter<? super R>> consumer) Deprecated. Use transformToUni(BiConsumer)
<R> Uni<R>	produceUni(Function<? super T,? extends Uni<? extends R>> mapper) Deprecated. Use transformToUni(Function) instead
<R> Uni<R>	transform(Function<? super T,? extends R> mapper) Produces a new Uni invoking the given function when the current Uni fires the item event.
<R> Multi<R>	transformToMulti(Function<? super T,? extends org.reactivestreams.Publisher<? extends R>> mapper) When this Uni produces its item (maybe null), call the given mapper to produce a Publisher.
<R> Uni<R>	transformToUni(BiConsumer<? super T,UniEmitter<? super R>> consumer) Transforms the received item asynchronously, forwarding the events emitted by an UniEmitter provided to the given consumer.
<R> Uni<R>	transformToUni(Function<? super T,? extends Uni<? extends R>> mapper) Transforms the received item asynchronously, forwarding the events emitted by another Uni produced by the given mapper.

Methods inherited from class java.lang.Object

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

Constructor Detail

UniOnItem

public UniOnItem(Uni<T> upstream)

Method Detail

invoke

public Uni<T> invoke(Consumer<? super T> callback)

Produces a new Uni invoking the given callback when the item event is fired. Note that the item can be null.

If the callback throws an exception, this exception is propagated to the downstream as failure.

Parameters:

callback - the callback, must not be null

Returns:

the new Uni

invokeUni

public Uni<T> invokeUni(Function<? super T,? extends Uni<?>> action)

Produces a new Uni invoking the given @{code action} when the item event is received. Note that the received item can be null.

Unlike invoke(Consumer), the passed function returns a Uni. When the produced Uni sends its item, this item is discarded, and the original item is forwarded downstream. If the produced Uni fails, the failure is propagated downstream.

Parameters:

action - the function taking the item and returning a Uni, must not be null, must not return null

Returns:

the new Uni

apply

@Deprecated
public <R> Uni<R> apply(Function<? super T,? extends R> mapper)

Deprecated. use transform(Function)

Produces a new Uni invoking the given function when the current Uni fires the item event. The function receives the item as parameter, and can transform it. The returned object is sent downstream as item.

For asynchronous composition, see transformToUni(Function).

Type Parameters:

R - the type of Uni item

Parameters:

mapper - the mapper function, must not be null

Returns:

the new Uni

transform

public <R> Uni<R> transform(Function<? super T,? extends R> mapper)

Produces a new Uni invoking the given function when the current Uni fires the item event. The function receives the item as parameter, and can transform it. The returned object is sent downstream as item.

For asynchronous composition, see transformToUni(Function).

Type Parameters:

R - the type of Uni item

Parameters:

mapper - the mapper function, must not be null

Returns:

the new Uni

transformToUni

public <R> Uni<R> transformToUni(Function<? super T,? extends Uni<? extends R>> mapper)

Transforms the received item asynchronously, forwarding the events emitted by another Uni produced by the given mapper.

The mapper is called with the item event of the current Uni and produces an Uni, possibly using another type of item (R). The events fired by produced Uni are forwarded to the Uni returned by this method.

This operation is generally named flatMap.

Type Parameters:

R - the type of item

Parameters:

mapper - the function called with the item of this Uni and producing the Uni, must not be null, must not return null.

Returns:

a new Uni that would fire events from the uni produced by the mapper function, possibly in an asynchronous manner.

produceUni

@Deprecated
public <R> Uni<R> produceUni(Function<? super T,? extends Uni<? extends R>> mapper)

Deprecated. Use transformToUni(Function) instead

Transforms the received item asynchronously, forwarding the events emitted by another Uni produced by the given mapper.

The mapper is called with the item event of the current Uni and produces an Uni, possibly using another type of item (R). The events fired by produced Uni are forwarded to the Uni returned by this method.

This operation is generally named flatMap.

Type Parameters:

R - the type of item

Parameters:

mapper - the function called with the item of this Uni and producing the Uni, must not be null, must not return null.

Returns:

a new Uni that would fire events from the uni produced by the mapper function, possibly in an asynchronous manner.

transformToMulti

public <R> Multi<R> transformToMulti(Function<? super T,? extends org.reactivestreams.Publisher<? extends R>> mapper)

When this Uni produces its item (maybe null), call the given mapper to produce a Publisher. Continue the pipeline with this publisher (as a Multi).

The mapper is called with the item event of the current Uni and produces a Publisher, possibly using another type of item (R). Events fired by the produced Publisher are forwarded to the Multi returned by this method.

This operation is generally named flatMapPublisher.

Type Parameters:

R - the type of item produced by the resulting Multi

Parameters:

mapper - the mapper, must not be null, may expect to receive null as item.

Returns:

the multi

produceMulti

@Deprecated
public <R> Multi<R> produceMulti(Function<? super T,? extends org.reactivestreams.Publisher<? extends R>> mapper)

Deprecated. Use transformToMulti(Function)

When this Uni produces its item (maybe null), call the given mapper to produce a Publisher. Continue the pipeline with this publisher (as a Multi).

The mapper is called with the item event of the current Uni and produces a Publisher, possibly using another type of item (R). Events fired by the produced Publisher are forwarded to the Multi returned by this method.

This operation is generally named flatMapPublisher.

Type Parameters:

R - the type of item produced by the resulting Multi

Parameters:

mapper - the mapper, must not be null, may expect to receive null as item.

Returns:

the multi

produceCompletionStage

@Deprecated
public <R> Uni<R> produceCompletionStage(Function<? super T,? extends CompletionStage<? extends R>> mapper)

Deprecated. Use transformToUni(Function) and produce the Uni using Uni.createFrom().completionStage(...)

Transforms the received item asynchronously, forwarding the events emitted by another CompletionStage produced by the given mapper.

The mapper is called with the item event of the current Uni and produces an CompletionStage, possibly using another type of item (R). The events fired by produced CompletionStage are forwarded to the Uni returned by this method.

*

Type Parameters:

R - the type of item

Parameters:

mapper - the function called with the item of this Uni and producing the CompletionStage, must not be null, must not return null.

Returns:

a new Uni that would fire events from the uni produced by the mapper function, possibly in an asynchronous manner.

transformToUni

public <R> Uni<R> transformToUni(BiConsumer<? super T,UniEmitter<? super R>> consumer)

Transforms the received item asynchronously, forwarding the events emitted by an UniEmitter provided to the given consumer.

The consumer is called with the item event of the current Uni and an emitter used to fire events. These events are these propagated by the produced Uni.

Type Parameters:

R - the type of item emitted by the emitter

Parameters:

consumer - the function called with the item of the this Uni and an UniEmitter. It must not be null.

Returns:

a new Uni that would fire events from the emitter consumed by the mapper function, possibly in an asynchronous manner.

produceUni

@Deprecated
public <R> Uni<R> produceUni(BiConsumer<? super T,UniEmitter<? super R>> consumer)

Deprecated. Use transformToUni(BiConsumer)

Transforms the received item asynchronously, forwarding the events emitted by an UniEmitter provided to the given consumer.

The consumer is called with the item event of the current Uni and an emitter used to fire events. These events are these propagated by the produced Uni.

Type Parameters:

R - the type of item emitted by the emitter

Parameters:

consumer - the function called with the item of the this Uni and an UniEmitter. It must not be null.

Returns:

a new Uni that would fire events from the emitter consumed by the mapper function, possibly in an asynchronous manner.

delayIt

public UniOnItemDelay<T> delayIt()

Produces a new Uni receiving an item from upstream and delaying the emission on the item event (with the same item).

Returns:

the object to configure the delay.

ignore

public UniOnItemIgnore<T> ignore()

Produces a Uni ignoring the item of the current Uni and continuing with either another item, a failure, or another Uni. The produced Uni propagates the failure event if the upstream uni fires a failure.

Examples:

 
     Uni<T> upstream = ...;
     uni = upstream.onItem().ignore().andSwitchTo(other) // Ignore the item from upstream and switch to another uni
     uni = upstream.onItem().ignore().andContinueWith(newResult) // Ignore the item from upstream, and fire newResult
 
 

Returns:

the object to configure the continuation logic.

failWith

public Uni<T> failWith(Function<? super T,? extends Throwable> mapper)

Produces a new Uni invoking the given function when the current Uni fires an item. The function transforms the received item into a failure that will be fired by the produced Uni. For asynchronous composition, see transformToUni(Function)}.

Parameters:

mapper - the mapper function, must not be null, must not return null

Returns:

the new Uni

castTo

public <O> Uni<O> castTo(Class<O> target)

Produces an Uni emitting an item based on the upstream item but casted to the target class.

Type Parameters:

O - the type of item emitted by the produced uni

Parameters:

target - the target class

Returns:

the new Uni

ifNull

public UniOnNull<T> ifNull()

Adds specific behavior when the observed Uni fires null as item. While null is a valid value, it may require specific processing. This group of operators allows implementing this specific behavior.

Examples:

 
     Uni<T> upstream = ...;
     Uni<T> uni = ...;
     uni = upstream.onItem().ifNull().continueWith(anotherValue) // use the fallback value if upstream emits null
     uni = upstream.onItem().ifNull().fail() // propagate a NullPointerException if upstream emits null
     uni = upstream.onItem().ifNull().failWith(exception) // propagate the given exception if upstream emits null
     uni = upstream.onItem().ifNull().switchTo(another) // switch to another uni if upstream emits null
 
 

Returns:

the object to configure the behavior when receiving null

ifNotNull

public UniOnNotNull<T> ifNotNull()

Adds specific behavior when the observed Uni fies a non-null item. If the item is null, default fallbacks are used.

Returns:

the object to configure the behavior when receiving a non-null item