OnJava8-Examples/generics/RandomList.java

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// generics/RandomList.java
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// <20>2016 MindView LLC: see Copyright.txt
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// We make no guarantees that this code is fit for any purpose.
// 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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public class RandomList<T> {
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private ArrayList<T> items = new ArrayList<>();
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private Random rand = new Random(47);
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public void add(T item) { items.add(item); }
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public T select() {
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return items.get(rand.nextInt(items.size()));
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}
public static void main(String[] args) {
RandomList<String> rs = new RandomList<>();
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Arrays.stream(
("The quick brown fox jumped over " +
"the lazy brown dog").split(" "))
.forEach(rs::add);
IntStream.range(0, 11).forEach(i ->
System.out.print(rs.select() + " "));
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}
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}
/* Output:
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brown over fox quick quick dog brown The brown lazy brown
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*/