Java Collections - Comparator.comparingLong() Examples

package com.logicbig.example.comparator;

import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

public class ComparingLongExample {

    public static void main(String... args) {
        List<Record> list = createExampleRecords();
        System.out.printf("before sort: %s%n", list);
        Collections.sort(list, Comparator.comparingLong(Record::getId));
        System.out.printf("after sort: %s%n", list);
    }

    private static List<Record> createExampleRecords() {
        return Arrays.asList(
                new Record(42000, "record 1"),
                new Record(21000, "record 2"),
                new Record(39000, "record 3")
        );
    }

    private static class Record {
        private long id;
        private String desc;

        public Record(long id, String desc) {
            this.id = id;
            this.desc = desc;
        }

        public long getId() {
            return id;
        }

        public String getDesc() {
            return desc;
        }

        @Override
        public String toString() {
            return "Record{" +
                    "id=" + id +
                    ", desc='" + desc + '\'' +
                    '}';
        }
    }
}