code: public AllWindowedStream<T, TimeWindow> timeWindowAll(Time size, Time slide) {
  		if (environment.getStreamTimeCharacteristic() == TimeCharacteristic.ProcessingTime) {
  			return windowAll(SlidingProcessingTimeWindows.of(size, slide));
  		} else {
  			return windowAll(SlidingEventTimeWindows.of(size, slide));
  		}
  	}
docs: Windows this {@code DataStream} into sliding time windows.
  
  <p>This is a shortcut for either {@code .window(SlidingEventTimeWindows.of(size, slide))} or
  {@code .window(SlidingProcessingTimeWindows.of(size, slide))} depending on the time characteristic
  set using
  {@link org.apache.flink.streaming.api.environment.StreamExecutionEnvironment#setStreamTimeCharacteristic(org.apache.flink.streaming.api.TimeCharacteristic)}
  
  <p>Note: This operation is inherently non-parallel since all elements have to pass through
  the same operator instance.
  
  @param size The size of the window.