hu.akarnokd.rxjava2.operators

Class ObservableTransformers

java.lang.Object

hu.akarnokd.rxjava2.operators.ObservableTransformers

public final class ObservableTransformers
extends java.lang.Object

Additional operators in the form of ObservableTransformer, use Observable.compose(ObservableTransformer) to apply the operators to an existing sequence.

Since:

0.18.2

See Also:

Observables

Method Summary

Modifier and Type	Method and Description
static <T,R> io.reactivex.ObservableTransformer<T,R>	errorJump(io.reactivex.ObservableTransformer<T,R> transformer) Allows an upstream error to jump over an inner transformation and is then reapplied once the inner transformation's returned Flowable terminates.
static <T,R> io.reactivex.ObservableTransformer<T,R>	flatMapDrop(io.reactivex.functions.Function<? super T,? extends io.reactivex.ObservableSource<? extends R>> mapper) FlatMap only one ObservableSource at a time and ignore upstream values until it terminates.
static <T,R> io.reactivex.ObservableTransformer<T,R>	flatMapLatest(io.reactivex.functions.Function<? super T,? extends io.reactivex.ObservableSource<? extends R>> mapper) FlatMap only one ObservableSource at a time and keep the latest upstream value until it terminates and resume with the ObservableSource mapped for that latest upstream value.
static <T> io.reactivex.ObservableTransformer<T,java.lang.Long>	indexOf(io.reactivex.functions.Predicate<? super T> predicate) Returns the first index of an element that matches a predicate or -1L if no elements match.
static <T> io.reactivex.ObservableTransformer<T,T>	observeOnDrop(io.reactivex.Scheduler scheduler) Schedules the event emission on a Scheduler and drops upstream values while the onNext with the current item is executing on that scheduler.
static <T> io.reactivex.ObservableTransformer<T,T>	observeOnLatest(io.reactivex.Scheduler scheduler) Schedules the event emission on a Scheduler and keeps the latest upstream item while the downstream's onNext is executing so that it will resume with that latest value.
static <T> io.reactivex.ObservableTransformer<T,T>	valve(io.reactivex.ObservableSource<java.lang.Boolean> other) Relays values until the other ObservableSource signals false and resumes if the other ObservableSource signals true again, like closing and opening a valve and not losing any items from the main source.
static <T> io.reactivex.ObservableTransformer<T,T>	valve(io.reactivex.ObservableSource<java.lang.Boolean> other, boolean defaultOpen) Relays values until the other ObservableSource signals false and resumes if the other ObservableSource signals true again, like closing and opening a valve and not losing any items from the main source and starts with the specified valve state.
static <T> io.reactivex.ObservableTransformer<T,T>	valve(io.reactivex.ObservableSource<java.lang.Boolean> other, boolean defaultOpen, int bufferSize) Relays values until the other ObservableSource signals false and resumes if the other ObservableSource signals true again, like closing and opening a valve and not losing any items from the main source and starts with the specified valve state and the specified buffer size hint.

Methods inherited from class java.lang.Object

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

Method Detail

indexOf

@SchedulerSupport(value="none")
 @CheckReturnValue
 @NonNull
public static <T> io.reactivex.ObservableTransformer<T,java.lang.Long> indexOf(@NonNull
                                                                                                                                               io.reactivex.functions.Predicate<? super T> predicate)

Returns the first index of an element that matches a predicate or -1L if no elements match.

Type Parameters:

T - the upstream element type

Parameters:

predicate - the predicate called to test each item, returning true will stop the sequence and return the current item index

Returns:

the new ObservableTransformer instance

Since:

0.18.2

observeOnDrop

@SchedulerSupport(value="custom")
 @CheckReturnValue
 @NonNull
public static <T> io.reactivex.ObservableTransformer<T,T> observeOnDrop(@NonNull
                                                                                                                                          io.reactivex.Scheduler scheduler)

Schedules the event emission on a Scheduler and drops upstream values while the onNext with the current item is executing on that scheduler.

Errors are delayed until all items that weren't dropped have been delivered.

Type Parameters:

T - the element type

Parameters:

scheduler - the scheduler to use for emitting events on

Returns:

the new ObservableTransformer instance

See Also:

observeOnLatest(Scheduler)

observeOnLatest

@SchedulerSupport(value="custom")
 @CheckReturnValue
 @NonNull
public static <T> io.reactivex.ObservableTransformer<T,T> observeOnLatest(@NonNull
                                                                                                                                            io.reactivex.Scheduler scheduler)

Schedules the event emission on a Scheduler and keeps the latest upstream item while the downstream's onNext is executing so that it will resume with that latest value.

Errors are delayed until the very last item has been delivered.

Type Parameters:

T - the element type

Parameters:

scheduler - the scheduler to use for emitting events on

Returns:

the new ObservableTransformer instance

See Also:

observeOnLatest(Scheduler)

flatMapDrop

@SchedulerSupport(value="none")
 @CheckReturnValue
 @NonNull
public static <T,R> io.reactivex.ObservableTransformer<T,R> flatMapDrop(io.reactivex.functions.Function<? super T,? extends io.reactivex.ObservableSource<? extends R>> mapper)

FlatMap only one ObservableSource at a time and ignore upstream values until it terminates.

Errors are delayed until both the upstream and the active inner ObservableSource terminate.

Type Parameters:

T - the upstream value type

R - the output type

Parameters:

mapper - the function that takes an upstream item and returns a ObservableSource to be run exclusively until it finishes

Returns:

the new ObservableTransformer instance

Since:

0.19.0

flatMapLatest

@SchedulerSupport(value="none")
 @CheckReturnValue
 @NonNull
public static <T,R> io.reactivex.ObservableTransformer<T,R> flatMapLatest(io.reactivex.functions.Function<? super T,? extends io.reactivex.ObservableSource<? extends R>> mapper)

FlatMap only one ObservableSource at a time and keep the latest upstream value until it terminates and resume with the ObservableSource mapped for that latest upstream value.

Errors are delayed until both the upstream and the active inner ObservableSource terminate.

Type Parameters:

T - the upstream value type

R - the output type

Parameters:

mapper - the function that takes an upstream item and returns a ObservableSource to be run exclusively until it finishes

Returns:

the new ObservableTransformer instance

Since:

0.19.0

errorJump

public static <T,R> io.reactivex.ObservableTransformer<T,R> errorJump(io.reactivex.ObservableTransformer<T,R> transformer)

Allows an upstream error to jump over an inner transformation and is then reapplied once the inner transformation's returned Flowable terminates.

Type Parameters:

T - the upstream value type

R - the downstream value type

Parameters:

transformer - the transformation applied to the flow on a per-Subscriber basis

Returns:

the new FlowableTransformer instance

Since:

0.19.1

valve

@SchedulerSupport(value="none")
public static <T> io.reactivex.ObservableTransformer<T,T> valve(io.reactivex.ObservableSource<java.lang.Boolean> other)

Relays values until the other ObservableSource signals false and resumes if the other ObservableSource signals true again, like closing and opening a valve and not losing any items from the main source.

Properties:

• The operator starts with an open valve.
• If the other ObservableSource completes, the sequence terminates with an IllegalStateException.
• The operator doesn't run on any particular Scheduler.
• The operator uses an internal unbounded buffer of size Flowable.bufferSize() to hold onto values if the valve is closed.

Type Parameters:

T - the value type of the main source

Parameters:

other - the other source

Returns:

the new ObservableTransformer instance

Throws:

java.lang.NullPointerException - if other is null

Since:

0.20.2

valve

@SchedulerSupport(value="none")
public static <T> io.reactivex.ObservableTransformer<T,T> valve(io.reactivex.ObservableSource<java.lang.Boolean> other,
                                                                                                 boolean defaultOpen)

Relays values until the other ObservableSource signals false and resumes if the other ObservableSource signals true again, like closing and opening a valve and not losing any items from the main source and starts with the specified valve state.

Properties:

• If the other ObservableSource completes, the sequence terminates with an IllegalStateException.
• The operator doesn't run on any particular Scheduler.
• The operator uses an internal unbounded buffer of size Flowable.bufferSize() to hold onto values if the valve is closed.

Type Parameters:

T - the value type of the main source

Parameters:

other - the other source

defaultOpen - should the valve start as open?

Returns:

the new ObservableTransformer instance

Throws:

java.lang.NullPointerException - if other is null

Since:

0.20.2

valve

@SchedulerSupport(value="none")
public static <T> io.reactivex.ObservableTransformer<T,T> valve(io.reactivex.ObservableSource<java.lang.Boolean> other,
                                                                                                 boolean defaultOpen,
                                                                                                 int bufferSize)

Relays values until the other ObservableSource signals false and resumes if the other ObservableSource signals true again, like closing and opening a valve and not losing any items from the main source and starts with the specified valve state and the specified buffer size hint.

Properties:

• If the other Publisher completes, the sequence terminates with an IllegalStateException.
• The operator doesn't run on any particular Scheduler.

Type Parameters:

T - the value type of the main source

Parameters:

other - the other source

defaultOpen - should the valve start as open?

bufferSize - the buffer size hint (the chunk size of the underlying unbounded buffer)

Returns:

the new ObservableTransformer instance

Throws:

java.lang.IllegalArgumentException - if bufferSize <= 0

java.lang.NullPointerException - if other is null

Since:

0.20.2