40 lines
1.2 KiB
Java
40 lines
1.2 KiB
Java
// arrays/ComparatorTest.java
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// (c)2017 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://OnJava8.com for more book information.
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// Implementing a Comparator for a class
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import java.util.*;
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import onjava.*;
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import static onjava.ArrayShow.*;
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class CompTypeComparator
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implements Comparator<CompType> {
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public int compare(CompType o1, CompType o2) {
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return (o1.j < o2.j ? -1 : (o1.j == o2.j ? 0 : 1));
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}
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}
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public class ComparatorTest {
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public static void main(String[] args) {
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CompType[] a = new CompType[12];
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Arrays.setAll(a, n -> CompType.get());
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show("Before sorting", a);
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Arrays.sort(a, new CompTypeComparator());
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show("After sorting", a);
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}
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}
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/* Output:
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Before sorting: [[i = 35, j = 37], [i = 41, j = 20], [i
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= 77, j = 79]
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, [i = 56, j = 68], [i = 48, j = 93], [i = 70, j = 7]
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, [i = 0, j = 25], [i = 62, j = 34], [i = 50, j = 82]
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, [i = 31, j = 67], [i = 66, j = 54], [i = 21, j = 6]
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]
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After sorting: [[i = 21, j = 6], [i = 70, j = 7], [i =
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41, j = 20]
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, [i = 0, j = 25], [i = 62, j = 34], [i = 35, j = 37]
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, [i = 66, j = 54], [i = 31, j = 67], [i = 56, j = 68]
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, [i = 77, j = 79], [i = 50, j = 82], [i = 48, j = 93]
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]
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*/
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