// streams/Reduce.java // (c)2017 MindView LLC: see Copyright.txt // We make no guarantees that this code is fit for any purpose. // Visit http://OnJava8.com for more book information. import java.util.*; import java.util.stream.*; class Frobnitz { int size; Frobnitz(int sz) { size = sz; } @Override public String toString() { return "Frobnitz(" + size + ")"; } // Generator: static Random rand = new Random(47); static final int BOUND = 100; static Frobnitz supply() { return new Frobnitz(rand.nextInt(BOUND)); } } public class Reduce { public static void main(String[] args) { Stream.generate(Frobnitz::supply) .limit(10) .peek(System.out::println) .reduce((fr0, fr1) -> fr0.size < 50 ? fr0 : fr1) .ifPresent(System.out::println); } } /* Output: Frobnitz(58) Frobnitz(55) Frobnitz(93) Frobnitz(61) Frobnitz(61) Frobnitz(29) Frobnitz(68) Frobnitz(0) Frobnitz(22) Frobnitz(7) Frobnitz(29) */