private long elapsedNanos() {
        return isRunning ? ticker.read() - startTick + elapsedNanos : elapsedNanos;
    }
Sets the elapsed time for this stopwatch to zero,
and places it in a stopped state.

@return this {@code Stopwatch} instance
lts-core/src/main/java/com/github/ltsopensource/core/commons/concurrent/limiter/Stopwatch.java