Package io.activej.csp

Interface ChannelSupplier<T>

All Superinterfaces:

io.activej.async.process.AsyncCloseable

All Known Implementing Classes:

AbstractChannelSupplier, ChannelFileReader, ChannelSuppliers.ChannelSupplierConcat, ChannelSuppliers.ChannelSupplierEmpty, ChannelSuppliers.ChannelSupplierOfException, ChannelSuppliers.ChannelSupplierOfIterator, ChannelSuppliers.ChannelSupplierOfValue

public interface ChannelSupplier<T>
extends io.activej.async.process.AsyncCloseable

This interface represents supplier of Promise of data that should be used serially (each consecutive get()) operation should be called only after previous get() operation finishes.

After supplier is closed, all subsequent calls to get() will return promise, completed exceptionally.

If any exception is caught while supplying data items, AsyncCloseable.closeEx(Exception) method should be called. All resources should be freed and the caught exception should be propagated to all related processes.

If get() returns Promise of null, it represents end-of-stream and means that no additional data should be queried.

Field Summary

Fields inherited from interface io.activej.async.process.AsyncCloseable

STATIC

Method Summary

Modifier and Type	Method	Description
default ChannelSupplier<T>	async()	Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier and makes its promise complete asynchronously.
default io.activej.promise.Promise<Void>	bindTo(ChannelInput<T> to)	Binds this ChannelSupplier to provided ChannelInput
default ChannelSupplier<T>	filter(Predicate<? super T> predicate)	Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier and checks if its Promise's value(s) match(es) the predicate, leaving only those value(s) which pass the test.
@NotNull io.activej.promise.Promise<T>	get()
default ChannelSupplier<T>	lenient()	Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier.
default <V> ChannelSupplier<V>	map(io.activej.common.function.FunctionEx<? super @NotNull T,? extends V> fn)	Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier and when its Promise completes, applies provided fn to the result.
default <V> ChannelSupplier<V>	mapAsync(Function<? super @NotNull T,io.activej.promise.Promise<V>> fn)	Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier and applies provided fn to its Promise asynchronously.
static <T> ChannelSupplier<T>	of()	Returns a ChannelSuppliers.ChannelSupplierEmpty.
static <T> ChannelSupplier<T>	of(io.activej.async.function.AsyncSupplier<T> supplier)
static <T> ChannelSupplier<T>	of(io.activej.async.function.AsyncSupplier<T> supplier, @Nullable io.activej.async.process.AsyncCloseable closeable)	Wraps AsyncSupplier in ChannelSupplier, when get() is called, AsyncSupplier's get() will be executed.
static <T> ChannelSupplier<T>	of(T value)	Wraps provided value to a ChannelSuppliers.ChannelSupplierOfValue.
static <T> ChannelSupplier<T>	of(T... values)
static <T> ChannelSupplier<T>	ofAnotherEventloop(@NotNull io.activej.eventloop.Eventloop anotherEventloop, @NotNull ChannelSupplier<T> anotherEventloopSupplier)
static <T> ChannelSupplier<T>	ofConsumer(Consumer<ChannelConsumer<T>> consumer, ChannelQueue<T> queue)	Returns a ChannelSupplier received from ChannelQueue.
static <T> ChannelSupplier<T>	ofException(Exception e)	Returns a ChannelSuppliers.ChannelSupplierOfException of provided exception.
static <T> ChannelSupplier<T>	ofIterator(Iterator<? extends T> iterator)	Wraps provided Iterator into ChannelSuppliers.ChannelSupplierOfIterator.
static <T> ChannelSupplier<T>	ofLazyProvider(Supplier<? extends ChannelSupplier<T>> provider)	Returns a ChannelSupplier wrapped in Supplier and calls its get() when get() method is called.
static <T> ChannelSupplier<T>	ofList(List<? extends T> list)
static <T> ChannelSupplier<T>	ofPromise(io.activej.promise.Promise<? extends ChannelSupplier<T>> promise)	Wraps promise of ChannelSupplier in ChannelSupplier or returns the ChannelSupplier from promise itself.
static ChannelSupplier<io.activej.bytebuf.ByteBuf>	ofSocket(AsyncTcpSocket socket)	Wraps AsyncTcpSocket.read() operation into ChannelSupplier
static <T> ChannelSupplier<T>	ofStream(Stream<? extends T> stream)
static <T> ChannelSupplier<T>	ofSupplier(Supplier<io.activej.promise.Promise<T>> supplier)	Wraps provided default Supplier to ChannelSupplier.
default ChannelSupplier<T>	peek(Consumer<? super T> fn)	Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier and when its Promise completes successfully, the result is accepted by the provided fn.
default io.activej.promise.Promise<Void>	streamTo(ChannelConsumer<T> consumer)
default io.activej.promise.Promise<Void>	streamTo(io.activej.promise.Promise<? extends ChannelConsumer<T>> consumer)
default <A, R> io.activej.promise.Promise<R>	toCollector(Collector<T,A,R> collector)
default io.activej.promise.Promise<List<T>>	toList()
default <R> R	transformWith(ChannelSupplierTransformer<T,R> fn)	Transforms this ChannelSupplier with the provided fn.
default ChannelSupplier<T>	until(Predicate<? super T> predicate)	Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier, when its get is called, its values will be returned until they don't fit the predicate.
default ChannelSupplier<T>	withEndOfStream(UnaryOperator<io.activej.promise.Promise<Void>> fn)
default ChannelSupplier<T>	withExecutor(io.activej.async.process.AsyncExecutor asyncExecutor)	Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier and makes its promise executed by the provided asyncExecutor.

Methods inherited from interface io.activej.async.process.AsyncCloseable

close, closeEx

Method Details

get

@NotNull
@NotNull io.activej.promise.Promise<T> get()

of

static <T> ChannelSupplier<T> of(io.activej.async.function.AsyncSupplier<T> supplier)

See Also:

• of(AsyncSupplier, AsyncCloseable)

of

static <T> ChannelSupplier<T> of(io.activej.async.function.AsyncSupplier<T> supplier,
 @Nullable
 @Nullable io.activej.async.process.AsyncCloseable closeable)

Wraps AsyncSupplier in ChannelSupplier, when get() is called, AsyncSupplier's get() will be executed.

Type Parameters:

T - data type wrapped in AsyncSupplier and ChannelSupplier

Parameters:

supplier - an AsyncSupplier to be wrapped in ChannelSupplier

closeable - a Cancellable which will be set for the ChannelSupplier wrapper

Returns:

ChannelSupplier which wraps AsyncSupplier

ofConsumer

static <T> ChannelSupplier<T> ofConsumer(Consumer<ChannelConsumer<T>> consumer,
 ChannelQueue<T> queue)

Returns a ChannelSupplier received from ChannelQueue.

ofSupplier

static <T> ChannelSupplier<T> ofSupplier(Supplier<io.activej.promise.Promise<T>> supplier)

Wraps provided default Supplier to ChannelSupplier.

of

static <T> ChannelSupplier<T> of()

Returns a ChannelSuppliers.ChannelSupplierEmpty.

of

static <T> ChannelSupplier<T> of(T value)

Wraps provided value to a ChannelSuppliers.ChannelSupplierOfValue.

Parameters:

value - a value to be wrapped in ChannelSupplier

Returns:

a ChannelSupplierOfValue which wraps the value

of

@SafeVarargs
static <T> ChannelSupplier<T> of(T... values)

See Also:

• ofIterator(Iterator)

ofException

static <T> ChannelSupplier<T> ofException(Exception e)

Returns a ChannelSuppliers.ChannelSupplierOfException of provided exception.

Parameters:

e - a Exception to be wrapped in ChannelSupplier

ofList

static <T> ChannelSupplier<T> ofList(List<? extends T> list)

See Also:

• ofIterator(Iterator)

ofStream

static <T> ChannelSupplier<T> ofStream(Stream<? extends T> stream)

See Also:

• ofIterator(Iterator)

ofIterator

static <T> ChannelSupplier<T> ofIterator(Iterator<? extends T> iterator)

Wraps provided Iterator into ChannelSuppliers.ChannelSupplierOfIterator.

Parameters:

iterator - an iterator to be wrapped in ChannelSupplier

Returns:

a ChannelSupplier which wraps elements of type

ofSocket

static ChannelSupplier<io.activej.bytebuf.ByteBuf> ofSocket(AsyncTcpSocket socket)

Wraps AsyncTcpSocket.read() operation into ChannelSupplier

Returns:

ChannelSupplier of ByteBufs that are read from network

ofPromise

static <T> ChannelSupplier<T> ofPromise(io.activej.promise.Promise<? extends ChannelSupplier<T>> promise)

Wraps promise of ChannelSupplier in ChannelSupplier or returns the ChannelSupplier from promise itself.

If promise is completed, it will be materialized and its result (a ChannelSupplier) will be returned.

Otherwise, when get() is called, it will wait until promise completes and promise result's (a ChannelSupplier) get() operation will be executed. If the promise completes exceptionally, a promise of exception will be returned.

Parameters:

promise - wraps a ChannelSupplier

Returns:

a ChannelSupplier of promise or a wrapper ChannelSupplier

ofAnotherEventloop

static <T> ChannelSupplier<T> ofAnotherEventloop(@NotNull
 @NotNull io.activej.eventloop.Eventloop anotherEventloop,
 @NotNull
 @NotNull ChannelSupplier<T> anotherEventloopSupplier)

ofLazyProvider

static <T> ChannelSupplier<T> ofLazyProvider(Supplier<? extends ChannelSupplier<T>> provider)

Returns a ChannelSupplier wrapped in Supplier and calls its get() when get() method is called.

Parameters:

provider - a provider of ChannelSupplier

Returns:

a ChannelSupplier that was wrapped in the provider

transformWith

default <R> R transformWith(ChannelSupplierTransformer<T,R> fn)

Transforms this ChannelSupplier with the provided fn.

Type Parameters:

R - returned result after transformation

Parameters:

fn - ChannelSupplierTransformer applied to the ChannelSupplier

async

default ChannelSupplier<T> async()

Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier and makes its promise complete asynchronously.

withExecutor

default ChannelSupplier<T> withExecutor(io.activej.async.process.AsyncExecutor asyncExecutor)

Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier and makes its promise executed by the provided asyncExecutor.

peek

default ChannelSupplier<T> peek(Consumer<? super T> fn)

Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier and when its Promise completes successfully, the result is accepted by the provided fn.

map

default <V> ChannelSupplier<V> map(io.activej.common.function.FunctionEx<? super @NotNull T,? extends V> fn)

Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier and when its Promise completes, applies provided fn to the result.

mapAsync

default <V> ChannelSupplier<V> mapAsync(Function<? super @NotNull T,io.activej.promise.Promise<V>> fn)

Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier and applies provided fn to its Promise asynchronously.

filter

default ChannelSupplier<T> filter(Predicate<? super T> predicate)

Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier and checks if its Promise's value(s) match(es) the predicate, leaving only those value(s) which pass the test.

until

default ChannelSupplier<T> until(Predicate<? super T> predicate)

Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier, when its get is called, its values will be returned until they don't fit the predicate. If one of the results passed the predicate test, consequent get operations will return null.

lenient

default ChannelSupplier<T> lenient()

Creates and returns a new AbstractChannelSupplier based on current ChannelSupplier. Even if its Promise completes with an exception, get() method will return a successfully completed Promise (in case of exception, with null result value).

streamTo

default io.activej.promise.Promise<Void> streamTo(ChannelConsumer<T> consumer)

See Also:

• ChannelSuppliers.streamTo(ChannelSupplier, ChannelConsumer)

streamTo

default io.activej.promise.Promise<Void> streamTo(io.activej.promise.Promise<? extends ChannelConsumer<T>> consumer)

bindTo

default io.activej.promise.Promise<Void> bindTo(ChannelInput<T> to)

Binds this ChannelSupplier to provided ChannelInput

toCollector

default <A,
R> io.activej.promise.Promise<R> toCollector(Collector<T,A,R> collector)

See Also:

• ChannelSuppliers.collect(io.activej.csp.ChannelSupplier<T>, A, io.activej.common.function.BiConsumerEx<A, T>, io.activej.common.function.FunctionEx<A, R>)

toList

default io.activej.promise.Promise<List<T>> toList()

See Also:

• toCollector(Collector)

withEndOfStream

default ChannelSupplier<T> withEndOfStream(UnaryOperator<io.activej.promise.Promise<Void>> fn)