题解 | #集合排序#

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Scanner;
import java.util.Comparator;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        Customer customer1 = new Customer("小明",scanner.nextInt());
        Customer customer2 = new Customer("小军",scanner.nextInt());
        Customer customer3 = new Customer("小红",scanner.nextInt());
        List<Customer> customers = new ArrayList<>();
        customers.add(customer1);
        customers.add(customer2);
        customers.add(customer3);
	  
	    // 函数式接口的写法
        customers.sort(Comparator.comparing(Customer::getConsumption).reversed());

        System.out.println(customers);

    }
}

class Customer {
    private String name;
    private int consumption;

    public Customer(String name, int consumption) {
        this.name = name;
        this.consumption = consumption;
    }

    @Override
    public String toString() {
        return "Customer{" +
                "name='" + name + '\'' +
                ", consumption=" + consumption +
                '}';
    }
    
    public int getConsumption () {
        return consumption;
    }

}

利用函数式接口的写法。