io.reactivex.rxjava3.observers

Class BaseTestConsumer<T,U extends BaseTestConsumer<T,U>>

java.lang.Object

io.reactivex.rxjava3.observers.BaseTestConsumer<T,U>

Type Parameters:

T - the value type consumed

U - the subclass of this BaseTestConsumer

Direct Known Subclasses:

TestObserver, TestSubscriber

public abstract class BaseTestConsumer<T,U extends BaseTestConsumer<T,U>>
extends Object

Base class with shared infrastructure to support TestSubscriber and TestObserver.

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	checkSubscriptionOnce
protected long	completions The number of completions.
protected CountDownLatch	done The latch that indicates an onError or onComplete has been called.
protected 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 List<T>	values The list of values received.

Constructor Summary

Constructors

Constructor and Description
BaseTestConsumer() Constructs a BaseTestConsumer with CountDownLatch set to 1.

Method Summary

Modifier and Type	Method and Description
U	assertComplete() Assert that this TestObserver/TestSubscriber received exactly one onComplete event.
U	assertEmpty() Assert that the TestObserver/TestSubscriber has received a Disposable/Subscription via onSubscribe but no other events.
U	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.
U	assertError(@NonNull Predicate<Throwable> errorPredicate) Asserts that this TestObserver/TestSubscriber received exactly one onError event for which the provided predicate returns true.
U	assertError(@NonNull Throwable error) Assert that this TestObserver/TestSubscriber received exactly the specified onError event value.
U	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.
U	assertNoErrors() Assert that this TestObserver/TestSubscriber has not received an onError event.
U	assertNotComplete() Assert that this TestObserver/TestSubscriber has not received an onComplete event.
U	assertNoValues() Assert that this TestObserver/TestSubscriber has not received any onNext events.
U	assertResult(T... values) Assert that the upstream signaled the specified values in order and completed normally.
protected abstract U	assertSubscribed() Assert that the onSubscribe method was called exactly once.
U	assertValue(@NonNull Predicate<T> valuePredicate) Asserts that this TestObserver/TestSubscriber received exactly one onNext value for which the provided predicate returns true.
U	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).
U	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.
U	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).
U	assertValueCount(int count) Assert that this TestObserver/TestSubscriber received the specified number onNext events.
U	assertValues(T... values) Assert that the TestObserver/TestSubscriber received only the specified values in the specified order.
U	assertValueSequence(@NonNull Iterable<? extends T> sequence) Assert that the TestObserver/TestSubscriber received only the specified sequence of values in the same order.
U	assertValuesOnly(T... values) Assert that the TestObserver/TestSubscriber received only the specified values in the specified order without terminating.
U	await() Awaits until this TestObserver/TestSubscriber receives an onError or onComplete events.
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.
U	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.
U	awaitDone(long time, @NonNull TimeUnit unit) Awaits until the internal latch is counted down.
protected abstract void	dispose() Cancel/dispose this test consumer.
protected @NonNull AssertionError	fail(@NonNull String message) Fail with the given message and add the sequence of errors as suppressed ones.
protected abstract boolean	isDisposed() Returns true if this test consumer was cancelled/disposed.
static @NonNull String	valueAndClass(@Nullable Object o) Appends the class name to a non-null value or returns "null".
@NonNull List<T>	values() Returns a shared list of received onNext values or the single onSuccess value.
U	withTag(@Nullable CharSequence tag) Set the tag displayed along with an assertion failure's other state information.

Methods inherited from class java.lang.Object

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

Field Detail

done

protected final CountDownLatch done

The latch that indicates an onError or onComplete has been called.

values

protected final List<T> values

The list of values received.

errors

protected final List<Throwable> errors

The list of errors received.

completions

protected long completions

The number of completions.

lastThread

protected Thread lastThread

The last thread seen by the observer.

checkSubscriptionOnce

protected boolean checkSubscriptionOnce

tag

protected CharSequence tag

The optional tag associated with this test consumer.

Since:

2.0.7

timeout

protected boolean timeout

Indicates that one of the awaitX method has timed out.

Since:

2.0.7

Constructor Detail

BaseTestConsumer

public BaseTestConsumer()

Constructs a BaseTestConsumer with CountDownLatch set to 1.

Method Detail

values

@NonNull
public final @NonNull List<T> values()

Returns a shared list of received onNext values or the single onSuccess value.

Note that accessing the items via certain methods of the List interface while the upstream is still actively emitting more items may result in a ConcurrentModificationException.

The List.size() method will return the number of items already received by this TestObserver/TestSubscriber in a thread-safe manner that can be read via List.get(int)) method (index range of 0 to List.size() - 1).

A view of the returned List can be created via List.subList(int, int) by using the bounds 0 (inclusive) to List.size() (exclusive) which, when accessed in a read-only fashion, should be also thread-safe and not throw any ConcurrentModificationException.

Returns:

a list of received onNext values

fail

@NonNull
protected final @NonNull AssertionError fail(@NonNull String message)

Fail with the given message and add the sequence of errors as suppressed ones.

Note this is deliberately the only fail method. Most of the times an assertion would fail but it is possible it was due to an exception somewhere. This construct will capture those potential errors and report it along with the original failure.

Parameters:

message - the message to use

Returns:

AssertionError the prepared AssertionError instance

await

@NonNull
public final U await()
                       throws InterruptedException

Awaits until this TestObserver/TestSubscriber receives an onError or onComplete events.

Returns:

this

Throws:

InterruptedException - if the current thread is interrupted while waiting

await

public final boolean await(long time,
        @NonNull TimeUnit unit)
                    throws InterruptedException

Awaits the specified amount of time or until this TestObserver/TestSubscriber receives an onError or onComplete events, whichever happens first.

Parameters:

time - the waiting time

unit - the time unit of the waiting time

Returns:

true if the TestObserver/TestSubscriber terminated, false if timeout happened

Throws:

InterruptedException - if the current thread is interrupted while waiting

assertComplete

@NonNull
public final U assertComplete()

Assert that this TestObserver/TestSubscriber received exactly one onComplete event.

Returns:

this

assertNotComplete

@NonNull
public final U assertNotComplete()

Assert that this TestObserver/TestSubscriber has not received an onComplete event.

Returns:

this

assertNoErrors

@NonNull
public final U assertNoErrors()

Assert that this TestObserver/TestSubscriber has not received an onError event.

Returns:

this

assertError

@NonNull
public final U assertError(@NonNull Throwable error)

Assert that this TestObserver/TestSubscriber received exactly the specified onError event value.

The comparison is performed via Objects.equals(Object, Object); since most exceptions don't implement equals(), this assertion may fail. Use the assertError(Class) overload to test against the class of an error instead of an instance of an error or assertError(Predicate) to test with different condition.

Parameters:

error - the error to check

Returns:

this

See Also:

assertError(Class), assertError(Predicate)

assertError

@NonNull
public final U 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.

Parameters:

errorClass - the error Class to expect

Returns:

this

assertError

@NonNull
public final U assertError(@NonNull Predicate<Throwable> errorPredicate)

Asserts that this TestObserver/TestSubscriber received exactly one onError event for which the provided predicate returns true.

Parameters:

errorPredicate - the predicate that receives the error Throwable and should return true for expected errors.

Returns:

this

assertValue

@NonNull
public final U assertValue(@NonNull 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).

Parameters:

value - the value to expect

Returns:

this

assertValue

@NonNull
public final U assertValue(@NonNull Predicate<T> valuePredicate)

Asserts that this TestObserver/TestSubscriber received exactly one onNext value for which the provided predicate returns true.

Parameters:

valuePredicate - the predicate that receives the onNext value and should return true for the expected value.

Returns:

this

assertValueAt

@NonNull
public final U assertValueAt(int index,
        @NonNull 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).

History: 2.1.3 - experimental

Parameters:

index - the position to assert on

value - the value to expect

Returns:

this

Since:

2.2

assertValueAt

@NonNull
public final U 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.

Parameters:

index - the position to assert on

valuePredicate - the predicate that receives the onNext value and should return true for the expected value.

Returns:

this

valueAndClass

@NonNull
public static @NonNull String valueAndClass(@Nullable Object o)

Appends the class name to a non-null value or returns "null".

Parameters:

o - the object

Returns:

the string representation

assertValueCount

@NonNull
public final U assertValueCount(int count)

Assert that this TestObserver/TestSubscriber received the specified number onNext events.

Parameters:

count - the expected number of onNext events

Returns:

this

assertNoValues

@NonNull
public final U assertNoValues()

Assert that this TestObserver/TestSubscriber has not received any onNext events.

Returns:

this

assertValues

@SafeVarargs
 @NonNull
public final U assertValues(@NonNull T... values)

Assert that the TestObserver/TestSubscriber received only the specified values in the specified order.

Parameters:

values - the values expected

Returns:

this

assertValuesOnly

@SafeVarargs
 @NonNull
public final U assertValuesOnly(@NonNull T... values)

Assert that the TestObserver/TestSubscriber received only the specified values in the specified order without terminating.

History: 2.1.4 - experimental

Parameters:

values - the values expected

Returns:

this

Since:

2.2

assertValueSequence

@NonNull
public final U assertValueSequence(@NonNull Iterable<? extends T> sequence)

Assert that the TestObserver/TestSubscriber received only the specified sequence of values in the same order.

Parameters:

sequence - the sequence of expected values in order

Returns:

this

assertSubscribed

@NonNull
protected abstract U assertSubscribed()

Assert that the onSubscribe method was called exactly once.

Returns:

this

assertResult

@SafeVarargs
 @NonNull
public final U assertResult(@NonNull T... values)

Assert that the upstream signaled the specified values in order and completed normally.

Parameters:

values - the expected values, asserted in order

Returns:

this

See Also:

assertFailure(Class, Object...)

assertFailure

@SafeVarargs
 @NonNull
public final U assertFailure(@NonNull Class<? extends Throwable> error,
        @NonNull T... values)

Assert that the upstream signaled the specified values in order and then failed with a specific class or subclass of Throwable.

Parameters:

error - the expected exception (parent) Class

values - the expected values, asserted in order

Returns:

this

awaitDone

@NonNull
public final U awaitDone(long time,
        @NonNull TimeUnit unit)

Awaits until the internal latch is counted down.

If the wait times out or gets interrupted, the TestObserver/TestSubscriber is cancelled.

Parameters:

time - the waiting time

unit - the time unit of the waiting time

Returns:

this

Throws:

RuntimeException - wrapping an InterruptedException if the wait is interrupted

assertEmpty

@NonNull
public final U assertEmpty()

Assert that the TestObserver/TestSubscriber has received a Disposable/Subscription via onSubscribe but no other events.

Returns:

this

withTag

@NonNull
public final U withTag(@Nullable CharSequence tag)

Set the tag displayed along with an assertion failure's other state information.

History: 2.0.7 - experimental

Parameters:

tag - the string to display (null won't print any tag)

Returns:

this

Since:

2.1

awaitCount

@NonNull
public final U 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.

History: 2.0.7 - experimental

Parameters:

atLeast - the number of items expected at least

Returns:

this

Since:

2.1

isDisposed

protected abstract boolean isDisposed()

Returns true if this test consumer was cancelled/disposed.

Returns:

true if this test consumer was cancelled/disposed.

dispose

protected abstract void dispose()

Cancel/dispose this test consumer.