如何通过姓名或科目来储存、删除数据，并最终按照科目来列出所有数据

Question

问题遇到的现象和发生背景

如何通过姓名或科目来储存、删除数据，并最终按照科目来列出所有数据

用代码块功能插入代码，请勿粘贴截图

package lab6;

import java.util.ArrayList;
import java.util.Scanner;

public class Manager {
    public static Scanner scanner = new Scanner(System.in);
    public static ArrayList<Student> students = new ArrayList<>();

    public static void main(String[] args) {
        while (true) {
            System.out.println("----------Gradebook-----------");
            System.out.println("--【1】Record student scores---");
            System.out.println("--【2】Delete student scores---");
            System.out.println("--【3】Search by the subject---");
            Student student = new Student();

            System.out.println("Enter your choice");
            String choice = scanner.next();
            switch (choice) {
                case "1":
                    student.addScore(students);
                    break;
                case "2":
                    student.deleteStudent(students);
                    break;
                case "3":
                    student.subject(students);
                default:
                    break;
            }
        }
    }
}





















package lab6;

import java.util.ArrayList;
import java.util.Scanner;

public class Student {
    public static Scanner scanner = new Scanner(System.in);
    private String name;
    private float math;
    private float english;
    public Student() {
    }

    public Student(String name, float math, float english ) {
        this.name = name;
        this.math = math;
        this.english = english;
        }
    
    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public float getMath() {
        return math;
    }

    public void setMath(float math) {
        this.math = math;
    }

    public float getEnglish() {
        return english;
    }

    public void setEnglish(float english) {
        this.english = english;
    }

    
    public void addScore(ArrayList<Student> students) {
        System.out.println("--Record student scores---");
        System.out.println("Please enter the following data in sequence:");
        String name;
        while (true) {
            System.out.println("name");
            name = scanner.next();
             break;    
        }
        
        System.out.println("Math");
        float math = scanner.nextFloat();
        System.out.println("English");
        float english = scanner.nextFloat();
       
        Student student = new Student();
        student.setName(name);
        student.setMath(math);
        student.setEnglish(english);
        students.add(student);
        System.out.println("Adding succeeded");
    }

     
    public void deleteStudent(ArrayList<Student> students) {
        System.out.println("--Delete student scores---");
        System.out.println("Enter the name of the student whose grade you want to delete");
            String name = scanner.next();

            int index = -1;
            for (int i = 0; i < students.size(); i++) {
                Student student = students.get(i);
                if (student.getName() == name) {
                    index = i;
                    break;
                }
            }
                students.remove(index);
                System.out.println("--Successfully deleted---");  
        }
    
    public void subject(ArrayList<Student> students) {
        System.out.println("--Search by the subject---");
        System.out.println("Please enter the subject you want to find");
            
        }

    

    

    }

运行结果及报错内容

Exception in thread "main" java.lang.IndexOutOfBoundsException: Index -1 out of bounds for length 0
at java.base/jdk.internal.util.Preconditions.outOfBounds(Preconditions.java:64)
at java.base/jdk.internal.util.Preconditions.outOfBoundsCheckIndex(Preconditions.java:70)
at java.base/jdk.internal.util.Preconditions.checkIndex(Preconditions.java:266)
at java.base/java.util.Objects.checkIndex(Objects.java:359)
at java.base/java.util.ArrayList.remove(ArrayList.java:504)
at lab6/lab6.Student.deleteStudent(Student.java:89)
at lab6/lab6.Manager.main(Manager.java:25)

我想要达到的结果

1.根据姓名添加成绩
2.按学生姓名和科目名称删除成绩
3.按照科目名称查询成绩，要能看到所有学生这一科的成绩

Answer 1

报错是数组越界问题。
if (student.getName() == name) 字符串的比较用equals方法