package com.study.demo10; import java.util.ArrayList; import java.util.Collections; import java.util.List; class Student { String name; int score; Student(String name, int score) { this.name = name; this.score = score; } @Override public String toString() { return "Student{name='" + name + "', score=" + score + "}"; } } public class LambdaCollection { public static void main(String[] args) { List students = new ArrayList<>(); students.add(new Student("张三", 85)); students.add(new Student("李四", 92)); students.add(new Student("王五", 78)); System.out.println("排序前:"); students.forEach(s -> System.out.println(s)); Collections.sort(students, (s1, s2) -> s2.score - s1.score); System.out.println("\n排序后(按成绩降序):"); students.forEach(s -> System.out.println(s)); } }