利用Redis进行数据存储

一时失言乱红尘 2024-03-25 23:10 85阅读 0赞

### **1.首先添加Redis依赖** ###

<dependency>
                <groupId>redis.clients</groupId>
                <artifactId>jedis</artifactId>
                <version>2.9.0</version>
            </dependency>

### **2.创建实体类** ###

public class User {
        private String uid;
        private String userName;
        private String password;
        private String name;
        //todo  get、set、toString、有参、无参构造方法

### **3.创建Dao层** ###

public class UserDao {
        //声明一个jedis
        private static Jedis jedis;
        /**
         * 添加一个有参构造方法
         */
        public UserDao(Jedis jedis){
            this.jedis=jedis;
        }
        /**
         * 添加
         */
        public void addUser(User user){
            //首先保存user-id
            jedis.sadd("useradd","user-"+user.getUid());
            //添加数据
            Map<String,String>map=new HashMap<>();
            map.put("uid",user.getUid());
            map.put("userName",user.getUserName());
            map.put("password",user.getPassword());
            map.put("name",user.getName());
            jedis.hmset("user-"+user.getUid(),map);
        }
        /**
         * 获取单个User
         */
        public List<String> getUserById(String id){
            if(exists()){
                return jedis.hmget("user-"+id,"id","userName","password","name");
            }
            return null;
        }
        /**
         * 获取全部
         */
        public List<User>getUserAll(){
            List<User>userList=new ArrayList<>();
            User user=null;
            if (exists()){
                for (String useradd:jedis.smembers("useradd")) {
                    user=new User();
                    List<String>lists=jedis.hmget(useradd,"id","userName","password","name");
                    user.setUid(lists.get(0));
                    user.setUserName(lists.get(1));
                    user.setPassword(lists.get(2));
                    user.setName(lists.get(3));
                    userList.add(user);
                }
                return userList;
            }
            return null;
        }
        /**
         * 删除全部
         */
        public boolean deleteAll(){
            if(exists()){
                jedis.del("useradd");
                return true;
            }
            return false;
        }
        /**
         * 判断是否存在
         */
        public boolean exists(){
            return jedis.exists("useradd");
        }
    }

### **4.创建测试类** ###

public class UserTest {
        private static Jedis jedis=null;
    
        public static void main(String[] args) {
            //连接本地Redis服务
            jedis=new Jedis("localhost");
            System.out.println("连接成功!");
            //查看服务是否正常运行
            System.out.println("服务正在运行"+jedis.ping());
            user();
        }
        public static void user(){
            UserDao userDao=new UserDao(jedis);
            userDao.deleteAll();
            userDao.addUser(new User("1","1班","123","张三"));
            userDao.addUser(new User("2","2班","456","李四"));
            userDao.addUser(new User("3","1班","789","王五"));
            userDao.addUser(new User("4","3班","147","老六"));
            for (User user:userDao.getUserAll()){
                System.out.println(user);
            }
        }
    }

本文链接：[https://blog.csdn.net/RHHcainiao/article/details/117526747][https_blog.csdn.net_RHHcainiao_article_details_117526747]

[https_blog.csdn.net_RHHcainiao_article_details_117526747]: https://blog.csdn.net/RHHcainiao/article/details/117526747