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[/b](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 String
name;
        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() {
            return
age;
        }
        public
void setAge(int age) {
            this.age = age;
        }
        public
int getJava() {
            return
java;
        }
        public
void setJava(int java) {
            this.java = java;
        }
        public
int getC_shar() {
            return
c_shar;
        }
        public
void setC_shar(int c_shar) {
            this.c_shar = c_shar;
        }
        public
int getHtml() {
            return
html;
        }
        public
void setHtml(int html) {
            this.html = html;
        }
        public
int getSql() {
            return
sql;
        }
        public
void setSql(int sql) {
            this.sql = sql;
        }
        public
int getSum() {
            return
sum;
        }
        public
void setSum() {
            this.sum =
this.java+this.sql+this.c_shar+this.html;
        }
        public
int getAvg() {
            return
avg;
        }
        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){
                return
true;
            }else{
                return
false;
            }
        }
        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);
    }
 
}