2015-12-02 09:20:27 -08:00
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// streams/Reduce.java
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2015-12-15 11:47:04 -08:00
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// (c)2016 MindView LLC: see Copyright.txt
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2015-12-02 09:20:27 -08:00
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// We make no guarantees that this code is fit for any purpose.
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// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
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import java.util.*;
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import java.util.stream.*;
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class Frobnitz {
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int size;
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Frobnitz(int sz) { size = sz; }
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@Override
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public String toString() {
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return "Frobnitz(" + size + ")";
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}
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// Generator:
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static Random rand = new Random(47);
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static final int bound = 100;
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static Frobnitz supply() {
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return new Frobnitz(rand.nextInt(bound));
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}
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}
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public class Reduce {
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public static void main(String[] args) {
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Stream.generate(Frobnitz::supply)
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.limit(10)
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.peek(System.out::println)
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.reduce((fr0, fr1) -> fr0.size < 50 ? fr0 : fr1)
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.ifPresent(System.out::println);
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}
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}
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/* Output:
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Frobnitz(58)
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Frobnitz(55)
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Frobnitz(93)
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Frobnitz(61)
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Frobnitz(61)
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Frobnitz(29)
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Frobnitz(68)
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Frobnitz(0)
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Frobnitz(22)
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Frobnitz(7)
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Frobnitz(29)
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*/
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