Q1

1 Student.java

package com.locreics;  
  
public class Student {  
    private String name;  
    private String className;  
    private int grades;  
  
    public Student(String name, String className, int grades) {  
        this.name = name;  
        this.className = className;  
        this.grades = grades;  
    }  
  
    public String getName() {  
        return name;  
    }  
  
    public int getGrades() {  
        return grades;  
    }  
  
    @Override  
    public String toString() {  
        return "Student{" +  
                "name='" + name + '\'' +  
                ", className='" + className + '\'' +  
                ", grades=" + grades +  
                '}';  
    }  
}

2 StudentSelect

package com.locreics;  
  
import java.util.Arrays;  
import java.util.Comparator;  
import java.util.List;  
  
public class StudentSelect {  
    public static void main(String[] args) {  
        List<Student> students = Arrays.asList(  
                new Student("张三", "Class A", 85),  
                new Student("李四", "Class A", 90),  
                new Student("王五", "Class B", 78),  
                new Student("赵六", "Class B", 88),  
                new Student("小明", "Class A", 92),  
                new Student("小红", "Class C", 70),  
                new Student("小刚", "Class C", 65),  
                new Student("小丽", "Class C", 80)  
        );  
  
        // --- Task 1: Print names of students with score >= 80 (Sorted by score descending) ---  
        System.out.println("Students with score >= 80 (Descending):");  
        students.stream()  
                .filter(s -> s.getGrades() >= 80)               // Filter scores >= 80  
                .sorted(Comparator.comparingInt(Student::getGrades).reversed()) // Sort descending  
                .map(Student::getName)                        // Extract only the name  
                .forEach(System.out::println);                // Print each name  
  
        System.out.println("\n----------------------------\n");  
  
        // --- Task 2: Calculate total score of all students ---  
        int totalScore = students.stream()  
                .mapToInt(Student::getGrades)                 // Convert Stream<Student> to IntStream  
                .sum();                                      // Sum all values  
  
        System.out.println("Total score of all students: " + totalScore);  
    }  
}