Numeric stream interfaces

As we have mentioned already, all three numeric interfaces, IntStream, LongStream, and DoubleStream, have methods similar to the methods in the Stream interface, including the methods of the Stream.Builder interface. This means that everything we have discussed so far in this chapter equally applies to any numeric stream interfaces. That is why, in this section, we will only talk about those methods that are not present in the Stream interface, as follows:

• The range(lower,upper) and rangeClosed(lower,upper) methods in the IntStream and LongStream interfaces allow you to create a stream from the values in the specified range.
• The boxed() and mapToObj() intermediate operations convert a numeric stream to Stream
• The mapToInt(), mapToLong(), and mapToDouble() intermediate operations convert a numeric stream of one type to a numeric stream of another type.
• The flatMapToInt(), flatMapToLong(), and flatMapToDouble() intermediate operations convert...