应用ArrayList实现某专业所有学生的成绩管理，要求构建学生（Student）类和成绩（AcademicRecord）类等，能够对不同年级的学生按总成绩排序并输出. Student(name,studID,major,grade, ArrayList< AcademicRecord > scores); AcademicRecord(studID,courseID,score) 要求学生类实现Comparable接口，排序按年级、成绩排； 并实现学生相同的判断（重写equals），当学生姓名和学号一样时，则学生相同。

首先，我们需要定义两个类，分别是学生类Student和成绩类AcademicRecord。具体代码如下：

public class Student implements Comparable<Student> {
    private String name;
    private String studID;
    private String major;
    private int grade;
    private ArrayList<AcademicRecord> scores;

    public Student(String name, String studID, String major, int grade, ArrayList<AcademicRecord> scores) {
        this.name = name;
        this.studID = studID;
        this.major = major;
        this.grade = grade;
        this.scores = scores;
    }

    public String getName() {
        return name;
    }

    public String getStudID() {
        return studID;
    }

    public String getMajor() {
        return major;
    }

    public int getGrade() {
        return grade;
    }

    public ArrayList<AcademicRecord> getScores() {
        return scores;
    }

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

    public void setStudID(String studID) {
        this.studID = studID;
    }

    public void setMajor(String major) {
        this.major = major;
    }

    public void setGrade(int grade) {
        this.grade = grade;
    }

    public void setScores(ArrayList<AcademicRecord> scores) {
        this.scores = scores;
    }

    @Override
    public int compareTo(Student o) {
        if (this.grade != o.grade) {
            return this.grade - o.grade;
        } else {
            int totalScore1 = getTotalScore(this.scores);
            int totalScore2 = getTotalScore(o.scores);
            return totalScore2 - totalScore1;
        }
    }

    private int getTotalScore(ArrayList<AcademicRecord> scores) {
        int total = 0;
        for (AcademicRecord record : scores) {
            total += record.getScore();
        }
        return total;
    }

    @Override
    public boolean equals(Object obj) {
        if (obj == null) {
            return false;
        }
        if (obj == this) {
            return true;
        }
        if (obj instanceof Student) {
            Student s = (Student) obj;
            return this.name.equals(s.name) && this.studID.equals(s.studID);
        }
        return false;
    }
}

public class AcademicRecord {
    private String studID;
    private String courseID;
    private int score;

    public AcademicRecord(String studID, String courseID, int score) {
        this.studID = studID;
        this.courseID = courseID;
        this.score = score;
    }

    public String getStudID() {
        return studID;
    }

    public String getCourseID() {
        return courseID;
    }

    public int getScore() {
        return score;
    }

    public void setStudID(String studID) {
        this.studID = studID;
    }

    public void setCourseID(String courseID) {
        this.courseID = courseID;
    }

    public void setScore(int score) {
        this.score = score;
    }
}

在学生类中，我们实现了Comparable接口，重写了compareTo方法，并且重写了equals方法，用于判断学生是否相同。在compareTo方法中，我们先按年级排序，如果年级相同，则按总成绩排序。

接下来，我们需要编写一个成绩管理类，用于对不同年级的学生按总成绩排序并输出。具体代码如下：

import java.util.ArrayList;
import java.util.Collections;

public class ScoreManager {
    private ArrayList<Student> students;

    public ScoreManager() {
        this.students = new ArrayList<>();
    }

    public void addStudent(Student student) {
        this.students.add(student);
    }

    public void sortByTotalScore(int grade) {
        ArrayList<Student> tmp = new ArrayList<>();
        for (Student student : students) {
            if (student.getGrade() == grade) {
                tmp.add(student);
            }
        }
        Collections.sort(tmp);
        for (Student student : tmp) {
            System.out.println(student.getName() + " " + student.getStudID() + " " + getTotalScore(student.getScores()));
        }
    }

    private int getTotalScore(ArrayList<AcademicRecord> scores) {
        int total = 0;
        for (AcademicRecord record : scores) {
            total += record.getScore();
        }
        return total;
    }
}

在成绩管理类中，我们提供了一个方法sortByTotalScore，用于对某个年级的学生按总成绩排序并输出。具体实现是先将该年级的学生筛选出来，然后调用Collections.sort方法进行排序，最后输出学生的姓名、学号和总成绩。

最后，我们来演示一下如何使用这些类：

public class Main {
    public static void main(String[] args) {
        ScoreManager manager = new ScoreManager();
        ArrayList<AcademicRecord> scores1 = new ArrayList<>();
        scores1.add(new AcademicRecord("001", "001", 90));
        scores1.add(new AcademicRecord("001", "002", 80));
        scores1.add(new AcademicRecord("001", "003", 70));
        ArrayList<AcademicRecord> scores2 = new ArrayList<>();
        scores2.add(new AcademicRecord("002", "001", 80));
        scores2.add(new AcademicRecord("002", "002", 70));
        scores2.add(new AcademicRecord("002", "003", 60));
        ArrayList<AcademicRecord> scores3 = new ArrayList<>();
        scores3.add(new AcademicRecord("003", "001", 70));
        scores3.add(new AcademicRecord("003", "002", 60));
        scores3.add(new AcademicRecord("003", "003", 50));
        manager.addStudent(new Student("张三", "001", "计算机科学与技术", 1, scores1));
        manager.addStudent(new Student("李四", "002", "计算机科学与技术", 2, scores2));
        manager.addStudent(new Student("王五", "003", "计算机科学与技术", 3, scores3));
        manager.sortByTotalScore(2);
    }
}

在main方法中，我们先创建一个成绩管理类ScoreManager，并且创建三个学生对象，分别属于不同的年级。然后将三个学生对象添加到成绩管理类中，并且调用sortByTotalScore方法进行排序和输出。这里我们演示的是对第二年级的学生按总成绩进行排序和输出。