（1）宣告Student類

屬性包括：學號，姓名，英語成績，數學成績，計算機成績，總成績

包括構造方法，get方法，set方法，toString方法，equal方法，compare方法，sum方法,testscore方法

public class Student {
    public int number;
    public double Egrade,Mgrade,Cgrade,Sumgrade,equalgrade,testscore;
    public String name;
    public Student() {
        
    }
    public
 
 void Student(int number,String name,double Egrade,double Mgrade,double Cgrade) {//構造方法
        this.number=number;
        this.name=name;
        this.Egrade=Egrade;
        this.Cgrade=Cgrade;
        this.Mgrade=Mgrade;
    }
    public int getnumber() {//get方法
        return number;
    }
    public
 
 String getname() {
        return name;
    }
    public double getEgrade() {
        return Egrade;
    }
    public double getMgrade() {
        return Mgrade;
    }
    public double getCgrade() {
        return Cgrade;
    }
    public double getSumgrade() {
        return Sumgrade;
    }
    public
 
 double getequalgrade() {
        return equalgrade;
    }
    public void setnumber(int number) {//set方法
        this.number=number;
    }
    public void setname(String name) {
        this.name=name;
    }
    public void setEgrade(double Egrade) {
        this.Egrade=Egrade;
    }
    public void setMgrade(double Mgrade) {
        this.Mgrade=Mgrade;
    }
    public void setCgrade(double Cgrade) {
        this.Cgrade=Cgrade;
    }
    public void setSumgrade(double Sumgrade) {
        this.Sumgrade=Sumgrade;
    }
    public void setequalgrade(double equalgrade) {
        this.equalgrade=equalgrade;
    }
    public void Sum() {//sum方法
        Sumgrade=Egrade+Mgrade+Cgrade;
    }
    public void equal() {//equal方法
        equalgrade=Sumgrade/3;
    }
    public void Compare(Student p) {//compare方法
        if(this.Sumgrade>p.Sumgrade) {
            System.out.println(this.name+"同學成績高");
        }
        else if(this.Sumgrade==p.Sumgrade) {
            System.out.println("兩位同學成績相同");
        }
        else
            System.out.println(p.name+"同學成績高");
    }
    public void testScore() {
        testscore=Sumgrade/3;
    }
    public String toString() {//toString方法
        return "Student [number=" + number + ", Egrade=" + Egrade + ", Mgrade=" + Mgrade + ", Cgrade=" + Cgrade
                + ", Sumgrade=" + Sumgrade + ", equalgrade=" + equalgrade + ", name=" + name + "]";
    }
}

此時的主函式呼叫為：

public class studentmain {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Student c1=new Student();
        Student c2=new Student();
        c1.setnumber(2019110105);
        c1.setname("chen");
        c1.setEgrade(87);
        c1.setMgrade(78);
        c1.setCgrade(84);
        c1.Sum();
        c1.equal();
        System.out.println("總成績為："+c1.getSumgrade());
        System.out.println("平均成績為："+c1.getequalgrade());
        System.out.println(c1.toString());
        c2.Student(2019110104, "fang", 70, 78, 94);
        c2.Sum();
        c2.equal();
        System.out.println(c2.toString());
        c1.Compare(c2);
    }

}

呼叫的結果為：

（2）宣告StudentXW類為Student的子類

新增一個屬性“zeren”，並且重寫testscore方法，使它等於三科的平均值加5

public class StudentXW extends Student{
    public String zeren;
    public void getzeren(String zeren) {
        this.zeren=zeren;
    }
    public String setzeren() {
        return zeren;
    }
    public void testScore() {
        testscore=Sumgrade/3+5;
    }

    public String toString() {
        return "StudentXW [name=" + name + ", number=" + number + ", Egrade=" + Egrade + ", Mgrade=" + Mgrade
                + ", Cgrade=" + Cgrade + ", Sumgrade=" + Sumgrade + ", equalgrade=" + equalgrade + ", testscore="
                + testscore + ", zeren=" + zeren + "]";
    }
    
}

（3）宣告StudentBZ類為Student的子類

跟上面Student相似，就是評測成績改變了而已

public class StudentBZ extends Student{
    public String zeren;
    public void getzeren(String zeren) {
        this.zeren=zeren;
    }
    public String setzeren() {
        return zeren;
    }
    public void testScore() {
        testscore=Sumgrade/3+5;
    }

    public String toString() {
        return "StudentXW [name=" + name + ", number=" + number + ", Egrade=" + Egrade + ", Mgrade=" + Mgrade
                + ", Cgrade=" + Cgrade + ", Sumgrade=" + Sumgrade + ", equalgrade=" + equalgrade + ", testscore="
                + testscore + ", zeren=" + zeren + "]";
    }
}

（4）測評程式碼為：

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Student c1=new Student();
        Student c2=new Student();
        c1.setnumber(2019110105);
        c1.setname("chen");
        c1.setEgrade(87);
        c1.setMgrade(78);
        c1.setCgrade(84);
        c1.Sum();
        c1.equal();
        System.out.println("總成績為："+c1.getSumgrade());
        System.out.println("平均成績為："+c1.getequalgrade());
        System.out.println(c1.toString());
        c2.Student(2019110104, "fang", 70, 78, 94);
        c2.Sum();
        c2.equal();
        System.out.println(c2.toString());
        c1.Compare(c2);
        StudentXW c3=new StudentXW();
        c3.Student(2019110106, "xi", 60, 78, 88);
        c3.getzeren("xuewei");
        c3.Sum();
        c3.testScore();
        System.out.println(c3.toString());
        StudentBZ c4=new StudentBZ();
        c4.Student(2019110109, "jin", 62, 78, 94);
        c4.getzeren("banzhang");
        c4.Sum();
        c4.equal();
        c4.testScore();
        System.out.println(c4.toString());
    }

（5）實驗結果為：