Java项目中如何实现学生成绩排序_Comparator与Comparable区别解析

public class Student implements Comparable<Student> {
    private String name;
    private double totalScore;

    public Student(String name, double totalScore) {
        this.name = name;
        this.totalScore = totalScore;
    }

    // 按总分升序排列
    @Override
    public int compareTo(Student other) {
        return Double.compare(this.totalScore, other.totalScore);
    }

    // Getter 方法
    public String getName() { return name; }
    public double getTotalScore() { return totalScore; }

    @Override
    public String toString() {
        return name + ": " + totalScore;
    }
}

List<Student> students = Arrays.asList(
    new Student("张三", 85.5),
    new Student("李四", 92.0),
    new Student("王五", 78.0)
);

Collections.sort(students); // 自动按总分升序
students.forEach(System.out::println);

// 按总分升序
Comparator<Student> byScoreAsc = (s1, s2) -> 
    Double.compare(s1.getTotalScore(), s2.getTotalScore());

// 按总分降序
Comparator<Student> byScoreDesc = (s1, s2) -> 
    Double.compare(s2.getTotalScore(), s1.getTotalScore());

// 按姓名字母顺序
Comparator<Student> byName = (s1, s2) -> 
    s1.getName().compareTo(s2.getName());

students.sort(byScoreDesc); // 按总分降序
students.forEach(System.out::println);

Comparator<Student> compound = byScoreDesc.thenComparing(byName);
students.sort(compound);

List<Student> sorted = students.stream()
    .sorted(byScoreDesc.thenComparing(byName))
    .collect(Collectors.toList());