src/main/java/io/reactivex/Flowable.java
@CheckReturnValue
    @BackpressureSupport(BackpressureKind.FULL)
    @SchedulerSupport(SchedulerSupport.COMPUTATION)
    public final ConnectableFlowable<T> replay(int bufferSize, long time, TimeUnit unit) {
        return replay(bufferSize, time, unit, Schedulers.computation());
    }
@CheckReturnValue
    @BackpressureSupport(BackpressureKind.FULL)
    @SchedulerSupport(SchedulerSupport.COMPUTATION)
    public final ConnectableFlowable<T> replay(int bufferSize, long time, TimeUnit unit) {
        return replay(bufferSize, time, unit, Schedulers.computation());
    }
@ CheckReturnValue @ BackpressureSupport ( BackpressureKind . FULL ) @ SchedulerSupport ( SchedulerSupport . COMPUTATION ) public final ConnectableFlowable < T > replay ( int bufferSize , long time , TimeUnit unit ) { return replay ( bufferSize , time , unit , Schedulers . computation ( ) ) ; }
Returns a {@link ConnectableFlowable} that shares a single subscription to the source Publisher and
replays at most {@code bufferSize} items that were emitted during a specified time window. A Connectable
Publisher resembles an ordinary Publisher, except that it does not begin emitting items when it is
subscribed to, but only when its {@code connect} method is called.
<p>
Note that due to concurrency requirements, {@code replay(bufferSize)} may hold strong references to more than
{@code bufferSize} source emissions.
<p>
<img width="640" height="515" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.nt.png" alt="">
<dl>
<dt><b>Backpressure:</b></dt>
<dd>This operator supports backpressure. Note that the upstream requests are determined by the child
Subscriber which requests the largest amount: i.e., two child Subscribers with requests of 10 and 100 will
request 100 elements from the underlying Publisher sequence.</dd>
<dt><b>Scheduler:</b></dt>
<dd>This version of {@code replay} operates by default on the {@code computation} {@link Scheduler}.</dd>
</dl>

@param bufferSize
the buffer size that limits the number of items that can be replayed
@param time
the duration of the window in which the replayed items must have been emitted
@param unit
the time unit of {@code time}
@return a {@link ConnectableFlowable} that shares a single subscription to the source Publisher and
replays at most {@code bufferSize} items that were emitted during the window defined by
{@code time}
@see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a>
Returns a { @link ConnectableFlowable } that shares a single subscription to the source Publisher and replays at most { @code bufferSize } items that were emitted during a specified time window . A Connectable Publisher resembles an ordinary Publisher except that it does not begin emitting items when it is subscribed to but only when its { @code connect } method is called . <p > Note that due to concurrency requirements { @code replay ( bufferSize ) } may hold strong references to more than { @code bufferSize } source emissions . <p > <img width = 640 height = 515 src = https : // raw . github . com / wiki / ReactiveX / RxJava / images / rx - operators / replay . nt . png alt = > <dl > <dt > <b > Backpressure : < / b > < / dt > <dd > This operator supports backpressure . Note that the upstream requests are determined by the child Subscriber which requests the largest amount : i . e . two child Subscribers with requests of 10 and 100 will request 100 elements from the underlying Publisher sequence . < / dd > <dt > <b > Scheduler : < / b > < / dt > <dd > This version of { @code replay } operates by default on the { @code computation } { @link Scheduler } . < / dd > < / dl >