MakeBooleanComparable.java

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/*
 * @test
 * @bug     4329937
 * @summary Basic test for making Boolean implement Comparable
 * @author  Josh Bloch
 * @key randomness
 */

import java.util.*;

public class MakeBooleanComparable {
    public static void main(String[] args) {
        Random rnd = new Random();
        List<Boolean> list = new ArrayList<>();
        int numFalse = 0;
        for (int i = 0; i < 1000; i++) {
            boolean element = rnd.nextBoolean();
            if (!element)
                numFalse++;
            list.add(element); // Autoboxing!
        }

        Collections.sort(list);

        for (int i = 0; i < numFalse; i++)
            if (list.get(i).booleanValue())  // Autounboxing doesn't work yet!
                throw new RuntimeException("False positive: " + i);
        for (int i = numFalse; i < 1000; i++)
            if (!list.get(i).booleanValue()) // Autounboxing doesn't work yet!
                throw new RuntimeException("False negative: " + i);
    }
}