javase项目 javase阶段小项目

1.需求分析

2. 配置
   项目文件
   
   环境：IDEA IntelliJ
   工具包 ：hutool-poi-apidocs
   工具包导入：
   右击项目文件
   
   open module settings
   
   
   3.具体实现
   （1)学生管理类StudentManager。java

import cn.hutool.poi.excel.ExcelReader;
import cn.hutool.poi.excel.ExcelUtil;
import cn.hutool.poi.excel.ExcelWriter;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

/**
 * ClassName StudentManager
 * Description
 *
 * @author 阿木木
 * @date 2020/12/26 10:26
 * Version 1.0
 */
public class StudentManager {
    static Scanner input = new Scanner(System.in);
    public static List<Student> studentArray = new ArrayList<>();

    /**
     *Description 显示主菜单
     **/
    public void showMenu(){
        do {
        Menu.showOperation();
        start();
            System.out.println("返回操作菜单：y/n？");
        } while ("y".equals(input.next()));

    }

    /**
     *Description 系统驱动类
     **/
    public void start(){
        switch (input.nextInt()){
            //增加学员信息
            case 1:{
                Student student = new Student();
                do {
                    if (addStudent(student)) {
                        System.out.println("增加学员成功");
                        //增加学员成功,显示成功加入的学员信息
                        System.out.println(studentArray);
                    } else {
                        System.out.println("增加学员失败");
                    }
                    System.out.println("是否继续增加：y/n？");
                }while ("y".equals(input.next()));
                //信息写入excel表格
                Excel.excelReader();
                //执行完一次增加操作，清空student对象数组
                studentArray.clear();
                break;
            }
            case 2:{
                //查询学生信息
                do{
                    System.out.print("请输入学号：");
                    Student student = findByNo(input.next());
                    if (student.getStudentNo() == null) {
                        System.out.println("该学号不存在");
                    }else {
                        System.out.println(student);
                    }
                    System.out.println("是否继续查询：y/n？");
                }while ("y".equals(input.next()));
                break;
            }

            case 3:{
                //更新学生信息
                do{
                    System.out.println("请输入要更新的学生信息");
                    updateStudent(inputInfo());
                    System.out.println("是否继续更新：y/n？");
                }while ("y".equals(input.next()));

                break;
            }

            case 4:{
                //删除学生信息
                do{
                System.out.println("请输入要删除的学号：");
                removeStudent(input.next());
                    System.out.println("是否继续删除：y/n？");
                }while ("y".equals(input.next()));
                break;
            }

            case 5:{
                System.out.println("谢谢使用！");
                //System.exit(int status)是中止当前虚拟机的运行，即强制性退出程序。status是状态码，0表示正常退出程序，其他值表示异常退出。
                System.exit(0);
                break;
            }
            default:{
                break;
            }

        }
    }

    /**
     *Description  case 1
     **/
    void case1(){
        Student student = new Student();
        do {
            if (addStudent(student)) {
                System.out.println("增加学员成功");
                //增加学员成功,显示成功加入的学员信息
                    System.out.println(studentArray);
            } else {
                System.out.println("增加学员失败");
            }
            System.out.println("是否继续增加：y/n？");
        }while ("y".equals(input.next()));
        //信息写入excel表格
        Excel.excelReader();
        //执行完一次增加操作，清空student对象数组
        studentArray.clear();
    }

    /**
     *Description case 2
     **/
    void case2(){
        //查询学生信息
        do{
            System.out.print("请输入学号：");
            Student student = findByNo(input.next());
            if (student.getStudentNo() == null) {
                System.out.println("该学号不存在");
            }else {
                System.out.println(student);
            }
            System.out.println("是否继续查询：y/n？");
        }while ("y".equals(input.next()));
    }

    /**
     *Description case 3
     **/
    void case3(){
        //更新学生信息
        do{
            System.out.println("请输入要更新的学生信息");
            updateStudent(inputInfo());
            System.out.println("是否继续更新：y/n？");
        }while ("y".equals(input.next()));

    }

    /**
     *Description case 4
     **/
    void case4(){
        System.out.println("请输入要删除的学号：");
        removeStudent(input.next());
    }

    /**
     *Description 添加学生对象到数组中
     **/
    boolean addStudent(Student student){
        student = inputInfo();
       // for (int i = 0; i < studentArray.size(); i++) {
            studentArray.add(student);
                return true;
       //     }
       // return false;

    }

    /**
     *Description 输入学生信息，并返回学生对象
     **/
    Student inputInfo(){

        Student student = new Student();

        System.out.print("请输入学号：");
        student.setStudentNo(input.next());

        System.out.print("请输入学生姓名：");
        student.setStudentName(input.next());

        System.out.print("请输入成绩：");
        student.setStudentScore(input.next());

        return student;

    }

    /**
     *Description 按学号查找学员信息
     **/
    Student findByNo(String stuNo) {
        ExcelReader excelReader = ExcelUtil.getReader("C:\\Users\\Administrator\\Desktop\\学生成绩表.xlsx");
        Student student = new Student();
        for (int i = 1; i < excelReader.getRowCount(); i++) {
            List<Object> objects = excelReader.readRow(i);
            if (objects != null) {
                String studentNo = objects.get(1).toString();
                if (stuNo.equals(studentNo)) {
                    student.setStudentName(objects.get(0).toString());
                    student.setStudentNo(studentNo);
                    student.setStudentScore(objects.get(2).toString());
                }
            }
        }
        return student;
    }

    /**
     *Description 更新学生数据
     **/
    void updateStudent(Student student){
        ExcelReader excelReader = ExcelUtil.getReader("C:\\Users\\Administrator\\Desktop\\学生成绩表.xlsx");
        for (int i = 1; i < excelReader.getRowCount(); i++) {
            List<Object> objects = excelReader.readRow(i);
            String studentNo =  objects.get(1).toString();
            if (student.getStudentNo().equals(studentNo)) {
                ExcelWriter excelWriter = ExcelUtil.getWriter("C:\\Users\\Administrator\\Desktop\\学生成绩表.xlsx");
                excelWriter.writeCellValue(0, i, student.getStudentName());
                excelWriter.writeCellValue(1, i, student.getStudentNo());
                excelWriter.writeCellValue(2, i, student.getStudentScore());
                excelWriter.flush();
                excelWriter.close();
                System.out.println("更新成功");
            }
        }
    }

    /**
     *Description 删除学生信息
     **/
    void removeStudent(String stuNo){
        ExcelReader excelReader = ExcelUtil.getReader("C:\\Users\\Administrator\\Desktop\\学生成绩表.xlsx");
        List<Object> objects = new ArrayList<>();
        for (int i = 1; i < excelReader.getRowCount(); i++) {
            objects = excelReader.readRow(i);
            if (objects.get(1).equals(stuNo)) {
                Workbook workbook = excelReader.getWorkbook();
                Sheet sheet = workbook.getSheetAt(0);
                Row row = sheet.getRow(i);
                sheet.removeRow(row);
                try {
                    workbook.write(new FileOutputStream("C:\\Users\\Administrator\\Desktop\\学生成绩表2.xlsx"));
                    workbook.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

（2）菜单类Menu.java

package com.studentscoresystem;

/**
 * ClassName Menu
 * Description
 *
 * @author 阿木木
 * @date 2020/12/26 10:37
 * Version 1.0
 */
public class Menu {

    /**
     *Description 输出学生信息管理系统操作
     **/
    static void showOperation(){
        System.out.println("+---------------学生信息管理系统--------------------+");
        System.out.println("|\t\t1.增加学员信息\t\t\t");
        System.out.println("|\t\t2.查找学员信息\t\t\t");
        System.out.println("|\t\t3.更新学员信息\t\t\t");
        System.out.println("|\t\t4.删除学员信息\t\t\t");
        System.out.println("|\t\t5.退出       \t\t\t");
        System.out.println("+-------------------------------------------------+");
        System.out.println("请选择操作项：（1）增加 （2）查找 （3）更新 （4）删除 （5） 注销");
    }


}

(3)学生信息数据类StudeBeam.java

/**
 * ClassName Student
 * Description
 *
 * @author 阿木木
 * @date 2020/12/26 10:49
 * Version 1.0
 */
public class Student {

    private String studentNo;
    private String studentName;
    private String studentScore;

    public String getStudentNo() {
        return studentNo;
    }

    public void setStudentNo(String studentNo) {
        this.studentNo = studentNo;
    }

    public String getStudentName() {
        return studentName;
    }

    public void setStudentName(String studentName) {
        this.studentName = studentName;
    }

    public String getStudentScore() {
        return studentScore;
    }

    public void setStudentScore(String studentScore) {
        this.studentScore = studentScore;
    }

    @Override
    public String toString() {
        return "学生信息：" +
                "学号" + studentNo + '\t' +
                "姓名：" + studentName + '\t' +
                "成绩：" + studentScore + "\t" ;
    }
}

(4)系统测试类Main.java

import java.util.Scanner;

/**
 * ClassName Main
 * Description 系统测试主类
 *
 * @author 阿木木
 * @date 2020/12/26 12:54
 * Version 1.0
 */
public class Main {
    static Scanner input = new Scanner(System.in);

    public static void main(String[] args) {
        StudentManager studentManager = new StudentManager();
        studentManager.showMenu();
    }
}

4.Excel

import cn.hutool.poi.excel.ExcelReader;
import cn.hutool.poi.excel.ExcelUtil;
import cn.hutool.poi.excel.ExcelWriter;

/**
 * ClassName Excel
 * Description
 *
 * @author 阿木木
 * @date 2020/12/28 19:42
 * Version 1.0
 */
public class Excel {

    /**
     *Description 数据写入excel
     **/
    static void excelReader(){
        for(Student student1:StudentManager.studentArray) {
            ExcelReader excelReader = ExcelUtil.getReader("C:\\Users\\Administrator\\Desktop\\学生成绩表.xlsx");
            ExcelWriter excelWriter = ExcelUtil.getWriter("C:\\Users\\Administrator\\Desktop\\学生成绩表.xlsx");
            int rowCount = excelReader.getRowCount();
            System.out.println(rowCount);
            excelWriter.writeCellValue(0, rowCount, student1.getStudentName());
            excelWriter.writeCellValue(1, rowCount, student1.getStudentNo());
            excelWriter.writeCellValue(2, rowCount, student1.getStudentScore());
            excelWriter.flush();
            excelWriter.close();
        }
    }

    /**
     *Description 读取excel数据
     **/
    static void excelWriter(){
        ExcelReader excelReader = ExcelUtil.getReader("C:\\Users\\Administrator\\Desktop\\学生成绩表.xlsx");

    }

}

5.测试截图.java

（1）增加

（2）减少

（3）更新

（4）删除