/**
* 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.internal.disposables;
import io.reactivex.*;
import io.reactivex.annotations.
Nullable;
import io.reactivex.internal.fuseable.
QueueDisposable;
/**
* Represents a stateless empty Disposable that reports being always
* empty and disposed.
* <p>It is also async-fuseable but empty all the time.
* <p>Since EmptyDisposable implements QueueDisposable and is empty,
* don't use it in tests and then signal onNext with it;
* use Disposables.empty() instead.
*/
public enum
EmptyDisposable implements
QueueDisposable<
Object> {
/**
* Since EmptyDisposable implements QueueDisposable and is empty,
* don't use it in tests and then signal onNext with it;
* use Disposables.empty() instead.
*/
INSTANCE,
/**
* An empty disposable that returns false for isDisposed.
*/
NEVER
;
@
Override
public void
dispose() {
// no-op
}
@
Override
public boolean
isDisposed() {
return this ==
INSTANCE;
}
public static void
complete(
Observer<?>
observer) {
observer.
onSubscribe(
INSTANCE);
observer.
onComplete();
}
public static void
complete(
MaybeObserver<?>
observer) {
observer.
onSubscribe(
INSTANCE);
observer.
onComplete();
}
public static void
error(
Throwable e,
Observer<?>
observer) {
observer.
onSubscribe(
INSTANCE);
observer.
onError(
e);
}
public static void
complete(
CompletableObserver observer) {
observer.
onSubscribe(
INSTANCE);
observer.
onComplete();
}
public static void
error(
Throwable e,
CompletableObserver observer) {
observer.
onSubscribe(
INSTANCE);
observer.
onError(
e);
}
public static void
error(
Throwable e,
SingleObserver<?>
observer) {
observer.
onSubscribe(
INSTANCE);
observer.
onError(
e);
}
public static void
error(
Throwable e,
MaybeObserver<?>
observer) {
observer.
onSubscribe(
INSTANCE);
observer.
onError(
e);
}
@
Override
public boolean
offer(
Object value) {
throw new
UnsupportedOperationException("Should not be called!");
}
@
Override
public boolean
offer(
Object v1,
Object v2) {
throw new
UnsupportedOperationException("Should not be called!");
}
@
Nullable
@
Override
public
Object poll() throws
Exception {
return null; // always empty
}
@
Override
public boolean
isEmpty() {
return true; // always empty
}
@
Override
public void
clear() {
// nothing to do
}
@
Override
public int
requestFusion(int
mode) {
return
mode &
ASYNC;
}
}