fluent comparing

P.java

package top.abosen.toys.ipv6;

import java.util.Comparator;
import java.util.List;
import java.util.concurrent.ThreadLocalRandom;
import java.util.function.Supplier;
import java.util.stream.Collectors;
import java.util.stream.IntStream;

/**
 * @author qiubaisen
 * @date 2020/7/23
 */
public class P {
    int a;
    long b;
    String c;

    public int getA() {
        return a;
    }

    public long getB() {
        return b;
    }

    public String getC() {
        return c;
    }

    public P(int a, long b, String c) {
        this.a = a;
        this.b = b;
        this.c = c;
    }

    @Override
    public String toString() {
        return String.format("P{a=%d, b=%d, c='%s'}", a, b, c);
    }

    public static void main(String[] args) {
        Comparator<P> congruent = (o1, o2) -> 0;
        ThreadLocalRandom localRandom = ThreadLocalRandom.current();

        Supplier<P> random = () -> new P(localRandom.nextInt(1,3), localRandom.nextLong(10,13),
                new String(new char[]{(char) localRandom.nextInt('a', 'c')}));
        List<P> origin = IntStream.range(0, 10).mapToObj(x -> random.get()).collect(Collectors.toList());
        List<P> result = origin.stream().sorted(congruent.thenComparing(P::getA).thenComparing(P::getB)
                .thenComparing(congruent.thenComparing(P::getC).reversed())
        ).collect(Collectors.toList());
        
        System.out.println(origin);
        System.out.println(result);
    }
}