Class TestSubscriber<T>

java.lang.Object

io.reactivex.rxjava4.observers.BaseTestConsumer<T, TestSubscriber<T>>

io.reactivex.rxjava4.subscribers.TestSubscriber<T>

Type Parameters:

T - the value type

All Implemented Interfaces:

FlowableSubscriber<T>, Flow.Subscriber<T>, Flow.Subscription

public class TestSubscriber<T>
extends BaseTestConsumer<T, TestSubscriber<T>>
implements FlowableSubscriber<T>, Flow.Subscription

A Flow.Subscriber implementation that records events and allows making assertions about them.

You can override the onSubscribe(Subscription), onNext(Object), onError(Throwable) and onComplete() methods but not the others (this is by design).

When calling the default request method, you are requesting on behalf of the wrapped actual Flow.Subscriber if any.

Field Summary

Fields inherited from class BaseTestConsumer

checkSubscriptionOnce, completions, done, errors, lastThread, tag, timeout, values

Modifier and Type	Field	Description
protected boolean	checkSubscriptionOnce
protected long	completions	The number of completions.
protected final CountDownLatch	done	The latch that indicates an onError or onComplete has been called.
protected final List<Throwable>	errors	The list of errors received.
protected Thread	lastThread	The last thread seen by the observer.
protected CharSequence	tag	The optional tag associated with this test consumer.
protected boolean	timeout	Indicates that one of the awaitX method has timed out.
protected final List<T>	values	The list of values received.

Constructor Summary

Constructors

Constructor	Description
TestSubscriber()	Constructs a non-forwarding TestSubscriber with an initial request value of Long.MAX_VALUE.
TestSubscriber(long initialRequest)	Constructs a non-forwarding TestSubscriber with the specified initial request value.
TestSubscriber(@NonNull Flow.Subscriber<? super T> downstream)	Constructs a forwarding TestSubscriber but leaves the requesting to the wrapped Flow.Subscriber.
TestSubscriber(@NonNull Flow.Subscriber<? super T> actual, long initialRequest)	Constructs a forwarding TestSubscriber with the specified initial request amount and an actual Flow.Subscriber to forward events to.

Method Summary

Modifier and Type	Method	Description
protected final TestSubscriber<T>	assertSubscribed()	Assert that the onSubscribe(Subscription) method was called exactly once.
final void	cancel()
static <T> @NonNull TestSubscriber<T>	create()	Creates a TestSubscriber with Long.MAX_VALUE initial request amount.
static <T> @NonNull TestSubscriber<T>	create(long initialRequested)	Creates a TestSubscriber with the given initial request amount.
static <T> TestSubscriber<T>	create(@NonNull Flow.Subscriber<? super T> delegate)	Constructs a forwarding TestSubscriber.
protected final void	dispose()	Cancel/dispose this test consumer.
final boolean	hasSubscription()	Returns true if this TestSubscriber received a Flow.Subscription via onSubscribe(Subscription).
final boolean	isCancelled()	Returns true if this TestSubscriber has been cancelled.
protected final boolean	isDisposed()	Returns true if this test consumer was cancelled/disposed.
void	onComplete()
void	onError(@NonNull Throwable t)
void	onNext(T t)
protected void	onStart()	Called after the onSubscribe is called and handled.
void	onSubscribe(@NonNull Flow.Subscription s)	Implementors of this method should make sure everything that needs to be visible in Flow.Subscriber.onNext(Object) is established before calling Flow.Subscription.request(long).
final void	request(long n)
final TestSubscriber<T>	requestMore(long n)	Calls request(long) and returns this.

Methods inherited from class BaseTestConsumer

assertComplete, assertEmpty, assertError, assertError, assertError, assertFailure, assertNoErrors, assertNotComplete, assertNoValues, assertResult, assertValue, assertValue, assertValueAt, assertValueAt, assertValueCount, assertValues, assertValueSequence, assertValuesOnly, await, await, awaitCount, awaitDone, fail, valueAndClass, values, withTag

Modifier and Type	Method	Description
final TestSubscriber<T>	assertComplete()	Assert that this TestObserver/TestSubscriber received exactly one onComplete event.
final TestSubscriber<T>	assertEmpty()	Assert that the TestObserver/TestSubscriber has received a Disposable/Subscription via onSubscribe but no other events.
final TestSubscriber<T>	assertError(@NonNull Predicate<Throwable> errorPredicate)	Asserts that this TestObserver/TestSubscriber received exactly one onError event for which the provided predicate returns true.
final TestSubscriber<T>	assertError(@NonNull Class<? extends Throwable> errorClass)	Asserts that this TestObserver/TestSubscriber received exactly one onError event which is an instance of the specified errorClass Class.
final TestSubscriber<T>	assertError(@NonNull Throwable error)	Assert that this TestObserver/TestSubscriber received exactly the specified onError event value.
final TestSubscriber<T>	assertFailure(@NonNull Class<? extends Throwable> error, T... values)	Assert that the upstream signaled the specified values in order and then failed with a specific class or subclass of Throwable.
final TestSubscriber<T>	assertNoErrors()	Assert that this TestObserver/TestSubscriber has not received an onError event.
final TestSubscriber<T>	assertNotComplete()	Assert that this TestObserver/TestSubscriber has not received an onComplete event.
final TestSubscriber<T>	assertNoValues()	Assert that this TestObserver/TestSubscriber has not received any onNext events.
final TestSubscriber<T>	assertResult(T... values)	Assert that the upstream signaled the specified values in order and completed normally.
final TestSubscriber<T>	assertValue(@NonNull Predicate<T> valuePredicate)	Asserts that this TestObserver/TestSubscriber received exactly one onNext value for which the provided predicate returns true.
final TestSubscriber<T>	assertValue(T value)	Assert that this TestObserver/TestSubscriber received exactly one onNext value which is equal to the given value with respect to Objects.equals(Object, Object).
final TestSubscriber<T>	assertValueAt(int index, @NonNull Predicate<T> valuePredicate)	Asserts that this TestObserver/TestSubscriber received an onNext value at the given index for the provided predicate returns true.
final TestSubscriber<T>	assertValueAt(int index, T value)	Asserts that this TestObserver/TestSubscriber received an onNext value at the given index which is equal to the given value with respect to null-safe Objects.equals(Object, Object).
final TestSubscriber<T>	assertValueCount(int count)	Assert that this TestObserver/TestSubscriber received the specified number onNext events.
final TestSubscriber<T>	assertValues(T... values)	Assert that the TestObserver/TestSubscriber received only the specified values in the specified order.
final TestSubscriber<T>	assertValueSequence(@NonNull Iterable<? extends T> sequence)	Assert that the TestObserver/TestSubscriber received only the specified sequence of values in the same order.
final TestSubscriber<T>	assertValuesOnly(T... values)	Assert that the TestObserver/TestSubscriber received only the specified values in the specified order without terminating.
final TestSubscriber<T>	await()	Awaits until this TestObserver/TestSubscriber receives an onError or onComplete events.
final boolean	await(long time, @NonNull TimeUnit unit)	Awaits the specified amount of time or until this TestObserver/TestSubscriber receives an onError or onComplete events, whichever happens first.
final TestSubscriber<T>	awaitCount(int atLeast)	Await until the TestObserver/TestSubscriber receives the given number of items or terminates by sleeping 10 milliseconds at a time up to 5000 milliseconds of timeout.
final TestSubscriber<T>	awaitDone(long time, @NonNull TimeUnit unit)	Awaits until the internal latch is counted down.
protected final @NonNull AssertionError	fail(@NonNull String message)	Fail with the given message and add the sequence of errors as suppressed ones.
static @NonNull String	valueAndClass(@Nullable Object o)	Appends the class name to a non-null value or returns "null".
final @NonNull List<T>	values()	Returns a shared list of received onNext values or the single onSuccess value.
final TestSubscriber<T>	withTag(@Nullable CharSequence tag)	Set the tag displayed along with an assertion failure's other state information.

Methods inherited from class Object

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

Constructor Details

TestSubscriber

public TestSubscriber()

Constructs a non-forwarding TestSubscriber with an initial request value of Long.MAX_VALUE.

TestSubscriber

public TestSubscriber(long initialRequest)

Constructs a non-forwarding TestSubscriber with the specified initial request value.

The TestSubscriber doesn't validate the initialRequest amount so one can test sources with invalid values as well.

Parameters:

initialRequest - the initial request amount

TestSubscriber

public TestSubscriber(@NonNull
 @NonNull Flow.Subscriber<? super T> downstream)

Constructs a forwarding TestSubscriber but leaves the requesting to the wrapped Flow.Subscriber.

Parameters:

downstream - the actual Subscriber to forward events to

TestSubscriber

public TestSubscriber(@NonNull
 @NonNull Flow.Subscriber<? super T> actual,
 long initialRequest)

Constructs a forwarding TestSubscriber with the specified initial request amount and an actual Flow.Subscriber to forward events to.

The TestSubscriber doesn't validate the initialRequest value so one can test sources with invalid values as well.

Parameters:

actual - the actual Subscriber to forward events to

initialRequest - the initial request amount

Method Details

create

@NonNull
public static <T> @NonNull TestSubscriber<T> create()

Creates a TestSubscriber with Long.MAX_VALUE initial request amount.

Type Parameters:

T - the value type

Returns:

the new TestSubscriber instance.

See Also:

• create(long)

create

@NonNull
public static <T> @NonNull TestSubscriber<T> create(long initialRequested)

Creates a TestSubscriber with the given initial request amount.

Type Parameters:

T - the value type

Parameters:

initialRequested - the initial requested amount

Returns:

the new TestSubscriber instance.

create

public static <T> TestSubscriber<T> create(@NonNull
 @NonNull Flow.Subscriber<? super T> delegate)

Constructs a forwarding TestSubscriber.

Type Parameters:

T - the value type received

Parameters:

delegate - the actual Flow.Subscriber to forward events to

Returns:

the new TestObserver instance

onSubscribe

public void onSubscribe(@NonNull
 @NonNull Flow.Subscription s)

Description copied from interface: FlowableSubscriber

Implementors of this method should make sure everything that needs to be visible in Flow.Subscriber.onNext(Object) is established before calling Flow.Subscription.request(long). In practice this means no initialization should happen after the request() call and additional behavior is thread safe in respect to onNext.

Specified by:

onSubscribe in interface Flow.Subscriber<T>

Specified by:

onSubscribe in interface FlowableSubscriber<T>

onStart

protected void onStart()

Called after the onSubscribe is called and handled.

onNext

public void onNext(@NonNull
 T t)

Specified by:

onNext in interface Flow.Subscriber<T>

onError

public void onError(@NonNull
 @NonNull Throwable t)

Specified by:

onError in interface Flow.Subscriber<T>

onComplete

public void onComplete()

Specified by:

onComplete in interface Flow.Subscriber<T>

request

public final void request(long n)

Specified by:

request in interface Flow.Subscription

cancel

public final void cancel()

Specified by:

cancel in interface Flow.Subscription

isCancelled

public final boolean isCancelled()

Returns true if this TestSubscriber has been cancelled.

Returns:

true if this TestSubscriber has been cancelled

dispose

protected final void dispose()

Description copied from class: BaseTestConsumer

Cancel/dispose this test consumer.

Specified by:

dispose in class BaseTestConsumer<T, TestSubscriber<T>>

isDisposed

protected final boolean isDisposed()

Description copied from class: BaseTestConsumer

Returns true if this test consumer was cancelled/disposed.

Specified by:

isDisposed in class BaseTestConsumer<T, TestSubscriber<T>>

Returns:

true if this test consumer was cancelled/disposed.

hasSubscription

public final boolean hasSubscription()

Returns true if this TestSubscriber received a Flow.Subscription via onSubscribe(Subscription).

Returns:

true if this TestSubscriber received a Flow.Subscription via onSubscribe(Subscription)

assertSubscribed

protected final TestSubscriber<T> assertSubscribed()

Assert that the onSubscribe(Subscription) method was called exactly once.

Specified by:

assertSubscribed in class BaseTestConsumer<T, TestSubscriber<T>>

Returns:

this

requestMore

public final TestSubscriber<T> requestMore(long n)

Calls request(long) and returns this.

History: 2.0.1 - experimental

Parameters:

n - the request amount

Returns:

this

Since:

2.1