Numeric stream interfaces

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

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