package studentscore;import java.io.Serializable;import java.util.*;/** * * 班級類 * grade    年級 * subject  專業 * className    班級 * number   人數 * stu      學生列表 */public class Classes  implements Serializable{    private String grade;    private String subject;    private String className;    private int number;    private ArrayList<Student> stu;    /**構造方法     */    public Classes(String grade, String subject, String className){        setGrade(grade);        setClassName(className);        setSubject(subject);        number = 0;        stu = new ArrayList<Student>();    }    public Classes(){        this("Default Grade", "Default Subject", "Default Class");    }    public Classes(Classes c){        this(c.getGrade(), c.getSubject(), c.getClassName());    }    /** setter & getter */    public String getGrade(){        return grade;    }    public String getClassName(){        return className;    }    public String getSubject(){        return subject;    }    public ArrayList getStudentList(){        return stu;    }    public int getNumber(){        return number;    }    public void setGrade(String grade){        this.grade = grade;    }    public void setClassName(String className){        this.className = className;    }    public void setSubject(String subject){        this.subject = subject;    }    public void setStudentList(ArrayList stu){        this.stu = stu;    }    public  void addNumber(){        number++;    }    public  void removeNumber(){        number--;    }    public void addStudent(Student stu){        this.getStudentList().add(stu);        addNumber();    }    public void removeStudent(Student stu){        this.getStudentList().remove(stu);        removeNumber();    }    @Override    public String toString(){        return this.getGrade() +  this.getSubject() + this.getClassName();    }    public boolean equels(Classes c){        if(this.getClassName().equals(c.getClassName()) && this.getGrade().equals(c.getGrade()) && this.getSubject().endsWith(c.getSubject()))            return true;        else            return false;    }}