src/main/java/io/reactivex/Flowable.java
@CheckReturnValue
    @BackpressureSupport(BackpressureKind.FULL)
    @SchedulerSupport(SchedulerSupport.CUSTOM)
    public final Flowable<T> takeLast(long time, TimeUnit unit, Scheduler scheduler, boolean delayError, int bufferSize) {
        return takeLast(Long.MAX_VALUE, time, unit, scheduler, delayError, bufferSize);
    }
@CheckReturnValue
    @BackpressureSupport(BackpressureKind.FULL)
    @SchedulerSupport(SchedulerSupport.CUSTOM)
    public final Flowable<T> takeLast(long time, TimeUnit unit, Scheduler scheduler, boolean delayError, int bufferSize) {
        return takeLast(Long.MAX_VALUE, time, unit, scheduler, delayError, bufferSize);
    }
Returns a Flowable that emits the items from the source Publisher that were emitted in a specified
window of time before the Publisher completed, where the timing information is provided by a specified
Scheduler.
<p>
<img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/takeLast.ts.png" alt="">
<dl>
<dt><b>Backpressure:</b></dt>
<dd>The operator honors backpressure from downstream and consumes the source {@code Publisher} in an
unbounded manner (i.e., no backpressure is applied to it) but note that this <em>may</em>
lead to {@code OutOfMemoryError} due to internal buffer bloat.
Consider using {@link #takeLast(long, long, TimeUnit, Scheduler)} in this case.</dd>
<dt><b>Scheduler:</b></dt>
<dd>You specify which {@link Scheduler} this operator will use.</dd>
</dl>

@param time
the length of the time window
@param unit
the time unit of {@code time}
@param scheduler
the Scheduler that provides the timestamps for the Observed items
@param delayError
if true, an exception signaled by the current Flowable is delayed until the regular elements are consumed
by the downstream; if false, an exception is immediately signaled and all regular elements dropped
@param bufferSize
the hint about how many elements to expect to be last
@return a Flowable that emits the items from the source Publisher that were emitted in the window of
time before the Publisher completed specified by {@code time}, where the timing information is
provided by {@code scheduler}
@see <a href="http://reactivex.io/documentation/operators/takelast.html">ReactiveX operators documentation: TakeLast</a>