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/**
* Copyright (c) 2016-present, RxJava Contributors.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software distributed under the License is
* distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See
* the License for the specific language governing permissions and limitations under the License.
*/
package io.reactivex.rxjava3.subscribers;
import java.util.concurrent.atomic.*;
import org.reactivestreams.*;
import io.reactivex.rxjava3.core.FlowableSubscriber;
import io.reactivex.rxjava3.internal.subscriptions.SubscriptionHelper;
import io.reactivex.rxjava3.observers.BaseTestConsumer;
/**
* A subscriber that records events and allows making assertions about them.
*
* You can override the onSubscribe, onNext, onError, onComplete, request and
* cancel methods but not the others (this is by design).
*
*
The TestSubscriber implements Disposable for convenience where dispose calls cancel.
*
*
When calling the default request method, you are requesting on behalf of the
* wrapped actual subscriber.
*
* @param the value type
*/
public class TestSubscriber
extends BaseTestConsumer>
implements FlowableSubscriber, Subscription {
/** The actual subscriber to forward events to. */
private final Subscriber downstream;
/** Makes sure the incoming Subscriptions get cancelled immediately. */
private volatile boolean cancelled;
/** Holds the current subscription if any. */
private final AtomicReference upstream;
/** Holds the requested amount until a subscription arrives. */
private final AtomicLong missedRequested;
/**
* Creates a TestSubscriber with Long.MAX_VALUE initial request.
* @param the value type
* @return the new TestSubscriber instance.
*/
public static TestSubscriber create() {
return new TestSubscriber();
}
/**
* Creates a TestSubscriber with the given initial request.
* @param the value type
* @param initialRequested the initial requested amount
* @return the new TestSubscriber instance.
*/
public static TestSubscriber create(long initialRequested) {
return new TestSubscriber(initialRequested);
}
/**
* Constructs a forwarding TestSubscriber.
* @param the value type received
* @param delegate the actual Subscriber to forward events to
* @return the new TestObserver instance
*/
public static TestSubscriber create(Subscriber delegate) {
return new TestSubscriber(delegate);
}
/**
* Constructs a non-forwarding TestSubscriber with an initial request value of Long.MAX_VALUE.
*/
public TestSubscriber() {
this(EmptySubscriber.INSTANCE, Long.MAX_VALUE);
}
/**
* Constructs a non-forwarding TestSubscriber with the specified initial request value.
* The TestSubscriber doesn't validate the initialRequest value so one can
* test sources with invalid values as well.
* @param initialRequest the initial request value
*/
public TestSubscriber(long initialRequest) {
this(EmptySubscriber.INSTANCE, initialRequest);
}
/**
* Constructs a forwarding TestSubscriber but leaves the requesting to the wrapped subscriber.
* @param downstream the actual Subscriber to forward events to
*/
public TestSubscriber(Subscriber downstream) {
this(downstream, Long.MAX_VALUE);
}
/**
* Constructs a forwarding TestSubscriber with the specified initial request value.
*
The TestSubscriber doesn't validate the initialRequest value so one can
* test sources with invalid values as well.
* @param actual the actual Subscriber to forward events to
* @param initialRequest the initial request value
*/
public TestSubscriber(Subscriber actual, long initialRequest) {
super();
if (initialRequest < 0) {
throw new IllegalArgumentException("Negative initial request not allowed");
}
this.downstream = actual;
this.upstream = new AtomicReference();
this.missedRequested = new AtomicLong(initialRequest);
}
@Override
public void onSubscribe(Subscription s) {
lastThread = Thread.currentThread();
if (s == null) {
errors.add(new NullPointerException("onSubscribe received a null Subscription"));
return;
}
if (!upstream.compareAndSet(null, s)) {
s.cancel();
if (upstream.get() != SubscriptionHelper.CANCELLED) {
errors.add(new IllegalStateException("onSubscribe received multiple subscriptions: " + s));
}
return;
}
downstream.onSubscribe(s);
long mr = missedRequested.getAndSet(0L);
if (mr != 0L) {
s.request(mr);
}
onStart();
}
/**
* Called after the onSubscribe is called and handled.
*/
protected void onStart() {
}
@Override
public void onNext(T t) {
if (!checkSubscriptionOnce) {
checkSubscriptionOnce = true;
if (upstream.get() == null) {
errors.add(new IllegalStateException("onSubscribe not called in proper order"));
}
}
lastThread = Thread.currentThread();
values.add(t);
if (t == null) {
errors.add(new NullPointerException("onNext received a null value"));
}
downstream.onNext(t);
}
@Override
public void onError(Throwable t) {
if (!checkSubscriptionOnce) {
checkSubscriptionOnce = true;
if (upstream.get() == null) {
errors.add(new NullPointerException("onSubscribe not called in proper order"));
}
}
try {
lastThread = Thread.currentThread();
errors.add(t);
if (t == null) {
errors.add(new IllegalStateException("onError received a null Throwable"));
}
downstream.onError(t);
} finally {
done.countDown();
}
}
@Override
public void onComplete() {
if (!checkSubscriptionOnce) {
checkSubscriptionOnce = true;
if (upstream.get() == null) {
errors.add(new IllegalStateException("onSubscribe not called in proper order"));
}
}
try {
lastThread = Thread.currentThread();
completions++;
downstream.onComplete();
} finally {
done.countDown();
}
}
@Override
public final void request(long n) {
SubscriptionHelper.deferredRequest(upstream, missedRequested, n);
}
@Override
public final void cancel() {
if (!cancelled) {
cancelled = true;
SubscriptionHelper.cancel(upstream);
}
}
/**
* Returns true if this TestSubscriber has been cancelled.
* @return true if this TestSubscriber has been cancelled
*/
public final boolean isCancelled() {
return cancelled;
}
@Override
protected final void dispose() {
cancel();
}
@Override
protected final boolean isDisposed() {
return cancelled;
}
// state retrieval methods
/**
* Returns true if this TestSubscriber received a subscription.
* @return true if this TestSubscriber received a subscription
*/
public final boolean hasSubscription() {
return upstream.get() != null;
}
// assertion methods
/**
* Assert that the onSubscribe method was called exactly once.
* @return this
*/
@Override
protected final TestSubscriber assertSubscribed() {
if (upstream.get() == null) {
throw fail("Not subscribed!");
}
return this;
}
/**
* Calls {@link #request(long)} and returns this.
* History: 2.0.1 - experimental
* @param n the request amount
* @return this
* @since 2.1
*/
public final TestSubscriber requestMore(long n) {
request(n);
return this;
}
/**
* A subscriber that ignores all events and does not report errors.
*/
enum EmptySubscriber implements FlowableSubscriber