Creating an Optional The Optional<T> class models the absence of a value by a special singleton returned by the Optional.empty()…
Finishing Adapter for Downstream Collectors The collectingAndThen() method encapsulates a downstream collector and a finisher function to allow the result…
Matching Elements The match operations determine whether any, all, or none of the stream elements satisfy a given Predicate. These…
Collecting to a Collection The method toCollection(Supplier) creates a collector that uses a mutable container of a specific Collection type…
Parallel Functional Reduction Parallel execution is illustrated in Figure 16.12. Multiple instances of the stream pipeline are executed in parallel,…
Implementing Mutable Reduction: The collect() Method The collect(Collector) method accepts a collector that encapsulates the functions required to perform a…
Finding the First or Any Element The findFirst() method can be used to find the first element that is available…
Apart from the for(:) loop at (2) to iterate over all elements of the list and read the number of…
Averaging Another common statistics to calculate is the average of values, defined as the sum of values divided by the…
Collecting to a ConcurrentMap If the collector returned by the Collectors.toMap() method is used in a parallel stream, the multiple…