The window() operator works almost the same, except that, instead of buffering items in a Collection object, it buffers items in another producer.

Here is an example:

    fun main(args: Array<String>) { 
      val flowable = Flowable.range(1,111)//(1) 
      flowable.window(10) 
        .subscribe { 
          flo->flo.subscribe {//(2) 
            print("$it, ") 
          } 
          println() 
       } 
    } 

Let's first see the output, as shown here, before we try to understand it:

The window operator buffers 10 emissions in a new Flowable instance, which we will again subscribe to inside the flowable.subscribe lambda, and print them with a comma as a suffix.

The window operator also has same functionality as the other overloads of the buffer operator.