io.prestosql.operator

Interface WorkProcessor<T>

public interface WorkProcessor<T>

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	WorkProcessor.Process<T>
static class	WorkProcessor.ProcessState<T>
static interface	WorkProcessor.Transformation<T,R>
static class	WorkProcessor.TransformationState<T>

Method Summary

Modifier and Type	Method and Description
static <T> WorkProcessor<T>	create(WorkProcessor.Process<T> process) Creates WorkProcessor from Process.
default WorkProcessor<T>	finishWhen(BooleanSupplier finishSignal)
default <R> WorkProcessor<R>	flatMap(Function<T,WorkProcessor<R>> mapper)
static <T> WorkProcessor<T>	flatten(WorkProcessor<WorkProcessor<T>> processor)
default <R> WorkProcessor<R>	flatTransform(WorkProcessor.Transformation<T,WorkProcessor<R>> transformation) Flattens WorkProcessors returned by transformation.
static <T> WorkProcessor<T>	fromIterable(Iterable<T> iterable)
static <T> WorkProcessor<T>	fromIterator(Iterator<T> iterator)
com.google.common.util.concurrent.ListenableFuture<?>	getBlockedFuture()
T	getResult() Get the result once the unit of work is done and the processor hasn't finished.
boolean	isBlocked()
boolean	isFinished()
default Iterator<T>	iterator() Converts WorkProcessor into an Iterator.
default <R> WorkProcessor<R>	map(Function<T,R> mapper)
static <T> WorkProcessor<T>	mergeSorted(Iterable<WorkProcessor<T>> processorIterable, Comparator<T> comparator)
static <T> WorkProcessor<T>	of(T... elements)
boolean	process() Call the method to progress the work.
default <R> WorkProcessor<R>	transform(WorkProcessor.Transformation<T,R> transformation) Transforms WorkProcessor using WorkProcessor.Transformation.
default <R> WorkProcessor<R>	transformProcessor(Function<WorkProcessor<T>,WorkProcessor<R>> transformation)
default WorkProcessor<T>	withProcessEntryMonitor(Runnable monitor)
default WorkProcessor<T>	withProcessStateMonitor(Consumer<WorkProcessor.ProcessState<T>> monitor)
default WorkProcessor<T>	yielding(BooleanSupplier yieldSignal) Makes WorkProcessor yield when given yieldSignal is set.
default Iterator<Optional<T>>	yieldingIterator() Converts WorkProcessor into an yielding Iterator.

Method Detail

process

boolean process()

Call the method to progress the work. When this method returns true then the processor is either finished or has a result available via getResult(). When this method returns false then the processor is either blocked or has yielded.

isBlocked

boolean isBlocked()

getBlockedFuture

com.google.common.util.concurrent.ListenableFuture<?> getBlockedFuture()

Returns:

a blocked future when isBlocked() returned true.

isFinished

boolean isFinished()

Returns:

true if the processor is finished. No more results are expected.

getResult

T getResult()

Get the result once the unit of work is done and the processor hasn't finished.

yielding

default WorkProcessor<T> yielding(BooleanSupplier yieldSignal)

Makes WorkProcessor yield when given yieldSignal is set. The processor is guaranteed to progress computations on subsequent process() calls even if yieldSignal is permanently on.

withProcessEntryMonitor

default WorkProcessor<T> withProcessEntryMonitor(Runnable monitor)

withProcessStateMonitor

default WorkProcessor<T> withProcessStateMonitor(Consumer<WorkProcessor.ProcessState<T>> monitor)

finishWhen

default WorkProcessor<T> finishWhen(BooleanSupplier finishSignal)

flatMap

default <R> WorkProcessor<R> flatMap(Function<T,WorkProcessor<R>> mapper)

map

default <R> WorkProcessor<R> map(Function<T,R> mapper)

flatTransform

default <R> WorkProcessor<R> flatTransform(WorkProcessor.Transformation<T,WorkProcessor<R>> transformation)

Flattens WorkProcessors returned by transformation. Each WorkProcessor produced by transformation will be fully consumed before transformation is called again to produce more processors.

transform

default <R> WorkProcessor<R> transform(WorkProcessor.Transformation<T,R> transformation)

Transforms WorkProcessor using WorkProcessor.Transformation. WorkProcessor.Transformation instance will be dereferenced immediately after WorkProcessor is exhausted.

transformProcessor

default <R> WorkProcessor<R> transformProcessor(Function<WorkProcessor<T>,WorkProcessor<R>> transformation)

iterator

default Iterator<T> iterator()

Converts WorkProcessor into an Iterator. The iterator will throw IllegalStateException when underlying WorkProcessor yields or becomes blocked. WorkProcessor instance will be dereferenced immediately after iterator is finished.

yieldingIterator

default Iterator<Optional<T>> yieldingIterator()

Converts WorkProcessor into an yielding Iterator. The iterator will throw IllegalStateException when underlying WorkProcessor becomes blocked. WorkProcessor instance will be dereferenced immediately after iterator is exhausted.

flatten

static <T> WorkProcessor<T> flatten(WorkProcessor<WorkProcessor<T>> processor)

of

@SafeVarargs
static <T> WorkProcessor<T> of(T... elements)

fromIterable

static <T> WorkProcessor<T> fromIterable(Iterable<T> iterable)

fromIterator

static <T> WorkProcessor<T> fromIterator(Iterator<T> iterator)

create

static <T> WorkProcessor<T> create(WorkProcessor.Process<T> process)

Creates WorkProcessor from Process. Process instance will be dereferenced immediately after WorkProcessor is finished.

mergeSorted

static <T> WorkProcessor<T> mergeSorted(Iterable<WorkProcessor<T>> processorIterable,
                                        Comparator<T> comparator)