63 lines
2.3 KiB
Java
63 lines
2.3 KiB
Java
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// collectionsindepth/SuppliersCollectionTest.java
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// (c)2016 MindView LLC: see Copyright.txt
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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.function.*;
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import java.util.stream.*;
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import onjava.*;
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class Government implements Supplier<String> {
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static String[] foundation = (
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"strange women lying in ponds distributing swords " +
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"is no basis for a system of government").split(" ");
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private int index;
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@Override
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public String get() { return foundation[index++]; }
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}
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public class SuppliersCollectionTest {
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public static void main(String[] args) {
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// The Suppliers class from the Generics chapter:
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Set<String> set = Suppliers.create(
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LinkedHashSet::new, new Government(), 15);
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System.out.println(set);
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List<String> list = Suppliers.create(
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LinkedList::new, new Government(), 15);
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System.out.println(list);
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list = new ArrayList<>();
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Suppliers.fill(list, new Government(), 15);
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System.out.println(list);
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// Or we could just use Streams:
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set = Arrays.stream(Government.foundation).collect(
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Collectors.toSet());
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System.out.println(set);
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list = Arrays.stream(Government.foundation).collect(
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Collectors.toList());
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System.out.println(list);
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list = Arrays.stream(Government.foundation).collect(
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Collectors.toCollection(LinkedList::new));
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System.out.println(list);
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set = Arrays.stream(Government.foundation).collect(
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Collectors.toCollection(LinkedHashSet::new));
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System.out.println(set);
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}
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}
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/* Output:
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[strange, women, lying, in, ponds, distributing, swords,
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is, no, basis, for, a, system, of, government]
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[strange, women, lying, in, ponds, distributing, swords,
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is, no, basis, for, a, system, of, government]
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[strange, women, lying, in, ponds, distributing, swords,
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is, no, basis, for, a, system, of, government]
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[ponds, no, a, in, swords, for, is, basis, strange,
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system, government, distributing, of, women, lying]
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[strange, women, lying, in, ponds, distributing, swords,
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is, no, basis, for, a, system, of, government]
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[strange, women, lying, in, ponds, distributing, swords,
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is, no, basis, for, a, system, of, government]
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[strange, women, lying, in, ponds, distributing, swords,
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is, no, basis, for, a, system, of, government]
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*/
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