Java学习-简单的用户管理系统

用户管理系统

• 实现基本的用户类，用于抽象出用户的基本信息(编号，姓名，性别，电话，邮件)–Student
• 实现用户工具类，用于实现用户的增、删、改、查–StudentUtils
• 测试类，用于测试使用–StudentTest

//Student类
public class Student {private int id;private String username;private String sex;private String telephone;private String email;public Student(int id, String username, String sex, String telephone, String email) {this.id = id;this.username = username;this.sex = sex;this.telephone = telephone;this.email = email;}public int getId() {return id;}public void setId(int id) {this.id = id;}public String getUsername() {return username;}public void setUsername(String username) {this.username = username;}public String getSex() {return sex;}public void setSex(String sex) {this.sex = sex;}public String getTelephone() {return telephone;}public void setTelephone(String telephone) {this.telephone = telephone;}public String getEmail() {return email;}public void setEmail(String email) {this.email = email;}@Overridepublic String toString() {return id +"\t    " + username + "\t  " + sex +"\t  " + telephone +"\t\t" + email ;}
}//StudentUtils类
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
//基于饿汉式单例模式实现类的单例创建
public class StudentUtils {private static StudentUtils studentUtils = new StudentUtils();private static List<Student> stuList = new ArrayList<>();private static int count = 0;public static StudentUtils getInstance() {return studentUtils;}private StudentUtils(){}//显示信息输出public void print() {System.out.println("-------------用户信息管理系统-------------");System.out.println("              1.添加用户");System.out.println("              2.修改用户");System.out.println("              3.删除用户");System.out.println("              4.用户列表");System.out.println("              5.退    出");System.out.println("              请选择(1-5)");}//添加用户信息public void addStu() {String username = getInput("请输入用户名");String sex = getInput("请输入性别");String telephone = getInput("请输入电话");String email = getInput("请输入邮件");Student stu = new Student(++count,username,sex,telephone,email);stuList.add(stu);}//修改用户信息public void updateStu() {String sid = getInput("请输入要修改用户的编号");int stuId = Integer.parseInt(sid) - 1;Student stu = stuList.get(stuId);String username = getInput("请输入用户名--" + stu.getUsername());String sex = getInput("请输入性别--" + stu.getSex());String telephone = getInput("请输入电话--" + stu.getTelephone());String email = getInput("请输入邮件--" + stu.getEmail());stu.setId(stu.getId());stu.setUsername(username);stu.setSex(sex);stu.setEmail(email);stuList.set(stuId,stu);}//删除用户public void delStu() {String sid = getInput("请输入要删除用户的编号");int stuId = Integer.parseInt(sid) - 1;if (stuId + 1 > count) {System.out.println("不存在的用户");return;}stuList.remove(stuId);System.out.println(sid + "号用户删除成功");this.printStuList();}//输出用户列表信息public void printStuList() {System.out.println("--------------用户列表--------------");System.out.printf("编号\t姓名\t性别\t电话\t\t邮件");System.out.println();if (count == 0) {System.out.println("目前还没有用户");return;}for (Student stu : stuList) {System.out.printf(stu.toString());System.out.println();}}public String getInput(String promptInfo) {System.out.println(promptInfo);Scanner scanner = new Scanner(System.in);String info = scanner.next();return info;}
}
//StudentTest类
import java.util.Scanner;
public class StudentTest {private static  boolean flag = true;public static void main(String[] args) {StudentUtils studentUtils = StudentUtils.getInstance();while (flag) {studentUtils.print();Scanner scanner = new Scanner(System.in);String inputSelect = scanner.next();try {int i = Integer.parseInt(inputSelect);if (i <= 0 || i > 5) {System.out.println("请输入1-5之间的数字");}} catch (NumberFormatException e) {System.out.println("请输入1-5之间的数字");}switch (inputSelect) {case "1":studentUtils.addStu();break;case "2":studentUtils.updateStu();break;case "3":studentUtils.delStu();break;case "4":studentUtils.printStuList();break;case "5":flag = false;break;}}}
}