给我写一个会员管理系统

好的，一个简单的会员管理系统可以包括以下功能：

1. 添加会员信息
2. 修改会员信息
3. 删除会员信息
4. 查询会员信息
5. 显示所有会员信息

以下是一个简单的Java会员管理系统实现，仅供参考：

import java.util.ArrayList;
import java.util.Scanner;

public class MemberManagementSystem {
    private ArrayList<Member> members = new ArrayList<Member>();
    private Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) {
        MemberManagementSystem system = new MemberManagementSystem();
        system.run();
    }

    public void run() {
        while (true) {
            System.out.println("=============会员管理系统=============");
            System.out.println("1. 添加会员信息");
            System.out.println("2. 修改会员信息");
            System.out.println("3. 删除会员信息");
            System.out.println("4. 查询会员信息");
            System.out.println("5. 显示所有会员信息");
            System.out.println("0. 退出系统");
            System.out.print("请输入您的选择：");

            int choice = scanner.nextInt();
            switch (choice) {
                case 1:
                    addMember();
                    break;
                case 2:
                    updateMember();
                    break;
                case 3:
                    deleteMember();
                    break;
                case 4:
                    queryMember();
                    break;
                case 5:
                    showAllMembers();
                    break;
                case 0:
                    System.out.println("感谢使用会员管理系统，再见！");
                    System.exit(0);
                default:
                    System.out.println("输入有误，请重新输入！");
                    break;
            }
        }
    }

    public void addMember() {
        System.out.print("请输入会员编号：");
        int id = scanner.nextInt();
        System.out.print("请输入会员姓名：");
        String name = scanner.next();
        System.out.print("请输入会员性别：");
        String gender = scanner.next();
        System.out.print("请输入会员年龄：");
        int age = scanner.nextInt();
        System.out.print("请输入会员电话：");
        String phone = scanner.next();

        Member member = new Member(id, name, gender, age, phone);
        members.add(member);
        System.out.println("添加会员信息成功！");
    }

    public void updateMember() {
        System.out.print("请输入需要修改的会员编号：");
        int id = scanner.nextInt();
        Member member = findMemberById(id);
        if (member == null) {
            System.out.println("会员编号不存在！");
            return;
        }

        System.out.print("请输入会员姓名：");
        String name = scanner.next();
        System.out.print("请输入会员性别：");
        String gender = scanner.next();
        System.out.print("请输入会员年龄：");
        int age = scanner.nextInt();
        System.out.print("请输入会员电话：");
        String phone = scanner.next();

        member.setName(name);
        member.setGender(gender);
        member.setAge(age);
        member.setPhone(phone);
        System.out.println("修改会员信息成功！");
    }

    public void deleteMember() {
        System.out.print("请输入需要删除的会员编号：");
        int id = scanner.nextInt();
        Member member = findMemberById(id);
        if (member == null) {
            System.out.println("会员编号不存在！");
            return;
        }

        members.remove(member);
        System.out.println("删除会员信息成功！");
    }

    public void queryMember() {
        System.out.print("请输入需要查询的会员编号：");
        int id = scanner.nextInt();
        Member member = findMemberById(id);
        if (member == null) {
            System.out.println("会员编号不存在！");
            return;
        }

        System.out.println("会员编号\t会员姓名\t会员性别\t会员年龄\t会员电话");
        System.out.println(member.getId() + "\t" + member.getName() + "\t" + member.getGender() + "\t" + member.getAge() + "\t" + member.getPhone());
    }

    public void showAllMembers() {
        System.out.println("会员编号\t会员姓名\t会员性别\t会员年龄\t会员电话");
        for (Member member : members) {
            System.out.println(member.getId() + "\t" + member.getName() + "\t" + member.getGender() + "\t" + member.getAge() + "\t" + member.getPhone());
        }
    }

    public Member findMemberById(int id) {
        for (Member member : members) {
            if (member.getId() == id) {
                return member;
            }
        }
        return null;
    }

    public static class Member {
        private int id;
        private String name;
        private String gender;
        private int age;
        private String phone;

        public Member(int id, String name, String gender, int age, String phone) {
            this.id = id;
            this.name = name;
            this.gender = gender;
            this.age = age;
            this.phone = phone;
        }

        public int getId() {
            return id;
        }

        public void setId(int id) {
            this.id = id;
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public String getGender() {
            return gender;
        }

        public void setGender(String gender) {
            this.gender = gender;
        }

        public int getAge() {
            return age;
        }

        public void setAge(int age) {
            this.age = age;
        }

        public String getPhone() {
            return phone;
        }

        public void setPhone(String phone) {
            this.phone = phone;
        }
    }
}

这个简单的Java会员管理系统实现了添加、修改、删除、查询和显示所有会员信息这些基本功能。当然，这只是一个简单的实现，您可以根据实际需要进行扩展和优化。