W3School TIY Editor

import java.util.ArrayList; import java.util.Collections; import java.util.Comparator; // 定义一个可比较的 Car 类 class Car implements Comparable { public String brand; public String model; public int year; public Car(String b, String m, int y) { brand = b; model = m; year = y; } // 定义该对象与其他对象的比较规则 public int compareTo(Object obj) { Car other = (Car)obj; if (year < other.year) return -1; // 当前对象年份较小 if (year > other.year) return 1; // 当前对象年份较大 return 0; // 两个对象年份相同 } } public class Main { public static void main(String[] args) { ArrayList<Car> myCars = new ArrayList<Car>(); myCars.add(new Car("BMW", "X5", 1999)); myCars.add(new Car("Honda", "Accord", 2006)); myCars.add(new Car("Ford", "Mustang", 1970)); Collections.sort(myCars); for (Car c : myCars) { System.out.println(c.brand + " " + c.model + " " + c.year); } } }