Java基础编程小练习---（数组）学生成绩管理系统

注：根据网络视频资源做的Java小编程

        

Tset类

import java.util.*;

public classtest {

    public static void main(String[] args){

        System.out.println("请输入定义的人数");

        Scannerin=newScanner(System.in);

        student[]stuArr=newstudent[in.nextInt()];

        AdminadminStu=newAdmin(); 

        while(true){

            System.out.println("----选择你要执行的功能-----");

            System.out.println("0:添加一个学生");

            System.out.println("1： 查找一个学生");

            System.out.println("2： 根据学生编号更新学生基本信息");

            System.out.println("3： 根据学生编号删除学生信息");

            System.out.println("4：  根据学生编号输入学生的个门成绩");

            System.out.println("5： 根据某门成绩进行排序");

            System.out.println("6： 根据总分进行排序");

            System.out.println("9： 退出系统");

            System.out.print("------------请输入对应操作编号：    ");

            int number=in.nextInt();

            if(number==0){

                System.out.println("请输入学生姓名：");

                Stringname=in.next();

                System.out.println("请输入学生年龄：");

                int age=in.nextInt();

                adminStu.create(name,age, stuArr);  //添加学生

                System.out.println();

            }else if(number==1){

                System.out.println("执行查找学生基本信息操作");

                System.out.print("请输入要查找的学生编号：");

                int on=in.nextInt();

                adminStu.select(on,stuArr);//查找学生

                System.out.println();

            }else if(number==2){

                System.out.println("执行更新学生基本信息操作");

                System.out.print("请输入要更新的学生编号：");

                int on=in.nextInt();

                System.out.print("请输入学生姓名：");

                Stringname=in.next();

                System.out.print("请输入学生年龄：");

                int age=in.nextInt();

                adminStu.update(on, name, age, stuArr);

                System.out.println();

            }else if(number==3){

                System.out.println("执行删除学生基本信息操作");

                System.out.print("请输入要删除的学生编号：");

                int on=in.nextInt();

                adminStu.delete(on,stuArr);

                System.out.println();

            }else if(number==4){

                System.out.println("执行输入学生成绩操作");

                System.out.print("请输入学生编号：");

                int on=in.nextInt();

                adminStu.input(on,stuArr);

                System.out.println();

            }else if(number==5){

                System.out.println("执行根据某课程成绩排序操作");

                System.out.println("请确定课程:  1. java    2. C# 3. HTML   4. SQL ");

                int num=in.nextInt();

                adminStu.courseSort(num,stuArr);

            }else if(number==6){

                System.out.println("执行根据总分成绩排序操作");

                adminStu.sort(stuArr);

               

            }else if(number==9){

                System.exit(0);

            }

           

        }

    }

}

Student类

public classstudent {

        private int on;

        private Stringname;

        private int age;

        private int java;

        private int c_shar;

        private int html;

        private int sql;

        private int sum;

        private int avg;

       

        public int getOn() {

            return this.on;

        }

        public void setOn(int on) {

            this.on = on;

        }

        public String getName() {

            return this.name;

        }

        public void setName(String name) {

            this.name = name;

        }

        public int getAge() {

            returnage;

        }

        public void setAge(int age) {

            this.age = age;

        }

        public int getJava() {

            returnjava;

        }

        public void setJava(int java) {

            this.java = java;

        }

        public int getC_shar() {

            returnc_shar;

        }

        public void setC_shar(int c_shar) {

            this.c_shar = c_shar;

        }

        public int getHtml() {

            returnhtml;

        }

        public void setHtml(int html) {

            this.html = html;

        }

        public int getSql() {

            returnsql;

        }

        public void setSql(int sql) {

            this.sql = sql;

        }

        public int getSum() {

            returnsum;

        }

        public void setSum() {

            this.sum =this.java+this.sql+this.c_shar+this.html;

        }

        public int getAvg() {

            returnavg;

        }

        public void setAvg() {

            this.avg =this.sum/4;

        }

       

        public String toString(){

             String msg="\t"+this.on+"\t"+this.name+"\t"+this.age+"\t"+this.java

                     +"\t"+this.c_shar+"\t"+this.html+"\t"+this.sql+"\t"+this.sum+"\t"+this.avg;

             return msg;

        }

       

       

}

Admin类

import java.util.Scanner;

public classAdmin {

    //用来管理学生的类

    Stringmsg="\t编号\t姓名\t年龄\tJava\tC#\tHTML\tSQL\t总分\t平均分";

    public void print(student[] arr){

        System.out.println(msg);

        for(int i=0;i<arr.length;i++){

            if(arr[i]!=null){      

                arr[i].setSum();

                arr[i].setAvg();

                System.out.println(arr[i]);

            }

        }

    }

    public boolean exist(int on,student stu){//判断学生是否存在

        if(stu!=null){

            if(stu.getOn()==on){

                returntrue;

            }else{

                returnfalse;

            }

        }

        return false;

 

    }

 

    public void create(String name,int age,student[] arr){

        studentstu=newstudent();

        stu.setName(name);

        stu.setAge(age);

        int i=this.setIndex(arr);

        stu.setOn(i);

        if(i==999){

            System.out.println("people over");

        }else{

            arr[i]=stu;

        }

        this.print(arr);

 

    }

    public int setIndex(student[]arr){ //返回数值为空的下标

        for(int i=0;i<arr.length;i++){

            if(arr[i]==null){

                return i;

            }

        }

        return 999 ;

    }

    public void select(int on,student[] arr){ 

        System.out.println(msg);

        for(int i=0;i<arr.length;i++){

            if(this.exist(on, arr[i])==true){

                //  System.out.println(msg);

                System.out.println(arr[i]);

                return;

            }

        }

        System.out.println("---people is not exist-----");

    }

    public void update(int on,String name,int age,student[] arr){

        for(int i=0;i<arr.length;i++){

            if(this.exist(on, arr[i])==true){

                arr[i].setName(name);

                arr[i].setAge(age);

                System.out.println("---update success----");

                this.print(arr);

                return;

            }

        }

        System.out.println("---people is not exist-----");

    }

    public void delete(int on,student[] arr){

        for(int i=0;i<arr.length;i++){

            if(this.exist(on, arr[i])==true){

                arr[i]=null;

                System.out.println("---delete success----");

                this.print(arr);

                return;

            }

        }

        System.out.println("---people is not exist-----");

    }

    public void input(int on,student[] arr){

        for(int i=0;i<arr.length;i++){

            if(this.exist(on, arr[i])==true){

                Scannerin=newScanner(System.in);

                System.out.print("编号为"+arr[i].getName()+"学生的Java成绩是: ");

                if(in.hasNextInt()){

                    arr[i].setJava(in.nextInt());

                }

                System.out.print("编号为"+arr[i].getName()+"学生的C#成绩是: ");

                if(in.hasNextInt()){

                    arr[i].setC_shar(in.nextInt());}

                System.out.print("编号为"+arr[i].getName()+"学生的HTML成绩是: ");

                if(in.hasNextInt()){

                    arr[i].setHtml(in.nextInt());}

                System.out.print("编号为"+arr[i].getName()+"学生的SQL成绩是: ");

                if(in.hasNextInt()){

                    arr[i].setSql(in.nextInt());}

                System.out.println("---input score success----");

                this.print(arr);

                return;

            }

        }

        System.out.println("---people is not exist-----");

    }

    public void courseSort(int num,student[] arr){

        if(num==1){

            for(int i=0;i<arr.length-1;i++){ //选择排序 思考这里为何不用冒泡排序

                for(int j=i+1;j<arr.length;j++){

                    if(arr[i]!=null&&arr[j]!=null){

                        if(arr[i].getJava()<arr[j].getJava()){

                            studentt=newstudent();

                            t=arr[i];

                            arr[i]=arr[j];

                            arr[j]=t;

                        }

                    }

 

                }

            }

        }else if(num==2){

            for(int i=0;i<arr.length-1;i++){

                for(int j=i+1;j<arr.length;j++){

                    if(arr[i]!=null&&arr[j]!=null){

                        if(arr[i].getC_shar()<arr[j].getC_shar()){

                            studentt=newstudent();

                            t=arr[i];

                            arr[i]=arr[j];

                            arr[j]=t;

                        }

                    }

 

                }

            }

        }else if(num==3){

            for(int i=0;i<arr.length-1;i++){

                for(int j=i+1;j<arr.length;j++){

                    if(arr[i]!=null&&arr[j]!=null){

                        if(arr[i].getHtml()<arr[j].getHtml()){

                            studentt=newstudent();

                            t=arr[i];

                            arr[i]=arr[j];

                            arr[j]=t;

                        }

                    }

 

                }

            }

        }else if(num==4){

            for(int i=0;i<arr.length-1;i++){

                for(int j=i+1;j<arr.length;j++){

                    if(arr[i]!=null&&arr[j]!=null){

                        if(arr[i].getSql()<arr[j].getSql()){

                            studentt=newstudent();

                            t=arr[i];

                            arr[i]=arr[j];

                            arr[j]=t;

                        }

                    }

 

                }

            }

        }else{

            System.out.println("输入的课程编号错误！");

        }

 

        this.print(arr);

    }

    public void sort(student[] arr){

        for(int i=0;i<arr.length-1;i++){ 

            for(int j=i+1;j<arr.length;j++){

                if(arr[i]!=null&&arr[j]!=null){

                    if(arr[i].getSum()<arr[j].getSum()){

                        studentt=newstudent();

                        t=arr[i];

                        arr[i]=arr[j];

                        arr[j]=t;

                    }

                }

 

            }

        }

        this.print(arr);

    }

 

}