/**
* 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.operators.observable;
import io.reactivex.*;
import io.reactivex.annotations.
Nullable;
import io.reactivex.functions.
Function;
import io.reactivex.internal.functions.
ObjectHelper;
import io.reactivex.internal.observers.
BasicFuseableObserver;
public final class
ObservableMap<T, U> extends
AbstractObservableWithUpstream<T, U> {
final
Function<? super T, ? extends U>
function;
public
ObservableMap(
ObservableSource<T>
source,
Function<? super T, ? extends U>
function) {
super(
source);
this.
function =
function;
}
@
Override
public void
subscribeActual(
Observer<? super U>
t) {
source.
subscribe(new
MapObserver<T, U>(
t,
function));
}
static final class
MapObserver<T, U> extends
BasicFuseableObserver<T, U> {
final
Function<? super T, ? extends U>
mapper;
MapObserver(
Observer<? super U>
actual,
Function<? super T, ? extends U>
mapper) {
super(
actual);
this.
mapper =
mapper;
}
@
Override
public void
onNext(T
t) {
if (
done) {
return;
}
if (
sourceMode !=
NONE) {
downstream.
onNext(null);
return;
}
U
v;
try {
v =
ObjectHelper.
requireNonNull(
mapper.
apply(
t), "The mapper function returned a null value.");
} catch (
Throwable ex) {
fail(
ex);
return;
}
downstream.
onNext(
v);
}
@
Override
public int
requestFusion(int
mode) {
return
transitiveBoundaryFusion(
mode);
}
@
Nullable
@
Override
public U
poll() throws
Exception {
T
t =
qd.
poll();
return
t != null ?
ObjectHelper.<U>
requireNonNull(
mapper.
apply(
t), "The mapper function returned a null value.") : null;
}
}
}