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;
      }
      @Override
      public 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 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;
              }
          }
      }
  }