• Redis入门(二)——基本操作


    Redis作为独立的服务端,在Java中去操作redis需要通过Redis提供的jar

    z在这里特别申明,除了基本数据以及String外,其余对象,要想写入redis,必须序列化(即使是对象也要实现序列化接口),且读取redis中的数据也需要反序列化

    不懂序列化的请自行百度

    下面是Demo代码

    Util类

    package com.redis.test.util;
    
    import java.util.ArrayList;
    import java.util.HashMap;
    import java.util.List;
    import java.util.Map;
    
    import com.redis.test.module.User;
    
    import redis.clients.jedis.Jedis;
    import redis.clients.jedis.JedisPool;
    import redis.clients.jedis.JedisPoolConfig;
    
    public class RedisTool {
        // Redis服务器地址
        private static String address = "127.0.0.1";
        // Redis服务器端口号
        private static int port = 6379;
    
        private static Jedis jedis;
    
        public static void main(String[] args) {
            RedisTool redisTool = new RedisTool();
            jedis = new Jedis(RedisTool.address, RedisTool.port);
            System.out.println("连接成功");
            redisTool.saveMap();
        }
    
        /**
         * 存储数组
         */
        public void saveList() {
            List<User> list = new ArrayList<User>();
            User user1 = new User();
            user1.setName("张三");
            user1.setPassword("123456");
            user1.setAddress("无锡市学前东路12号");
            user1.setAge(23);
            list.add(user1);
    
            User user2 = new User();
            user2.setName("李四");
            user2.setPassword("123456");
            user2.setAddress("无锡市仁爱路89号");
            user2.setAge(18);
            list.add(user2);
    
            jedis.set(("userList").getBytes(), SerializeUtil.serialize(list));
            byte[] userObjs = jedis.get(("userList").getBytes());
            List<Object> userList = (List<Object>) SerializeUtil.unserialize(userObjs);
            System.out.println(userList.size());
        }
    
        /**
         * 存储对象
         */
        public void saveObject() {
    
            User user = new User();
            user.setName("张三");
            user.setPassword("123456");
            user.setAddress("无锡市学前东路12号");
            user.setAge(23);
            jedis.set("user".getBytes(), SerializeUtil.serialize(user));
            System.out.println("Jedis中存储的字符串为:" + jedis.get("test"));
            byte[] userObj = jedis.get(("user").getBytes());
            user = (User) SerializeUtil.unserialize(userObj);
            System.out.println(user.toString());
        }
        
        /**
         * 存储Map
         */
        public void saveMap() {
            Map<String , String> map = new HashMap<String, String>();
            map.put("name", "你好");
            jedis.set("map".getBytes(), SerializeUtil.serialize(map));
            byte[] mapObj = jedis.get(("map").getBytes());
            Map newMap = (Map) SerializeUtil.unserialize(mapObj);
            System.out.println(newMap.get("name").toString());
        }
    }

    序列化工具类:

    package com.redis.test.util;
    
    import java.io.ByteArrayInputStream;
    import java.io.ByteArrayOutputStream;
    import java.io.Closeable;
    import java.io.IOException;
    import java.io.ObjectInputStream;
    import java.io.ObjectOutputStream;
    import java.util.ArrayList;
    import java.util.List;
    
    public class SerializeUtil {
        public static byte[] serialize(Object object) {
            ObjectOutputStream oos = null;
            ByteArrayOutputStream baos = null;
            byte[] bytes = null;
            if(null!=object){
                try {
                    baos = new ByteArrayOutputStream();
                    oos = new ObjectOutputStream(baos);
                    oos.writeObject(object);
                    bytes = baos.toByteArray();
                } catch (Exception e) {
                        e.printStackTrace();
                }
            }
            return bytes;
        }
    
        public static Object unserialize(byte[] bytes) {
            ByteArrayInputStream bais = null;
            try {
                // 反序列化
                bais = new ByteArrayInputStream(bytes);
                ObjectInputStream ois = new ObjectInputStream(bais);
                return ois.readObject();
            } catch (Exception e) {
                e.printStackTrace();
            } finally {  
                close(bais);
            }
            return null;
        }
        
        /**
         * 列表序列化(用于Redis整存整取)
         * @param value
         * @return
         */
        public static <T> byte[] serializeList(List<T> value) {  
            if (value == null) {
                throw new NullPointerException("Can't serialize null");  
            }
            byte[] rv=null;  
            ByteArrayOutputStream bos = null;  
            ObjectOutputStream os = null;  
            try {  
                bos = new ByteArrayOutputStream();  
                os = new ObjectOutputStream(bos);  
                for(T obj : value){  
                    os.writeObject(obj);  
                }  
                os.writeObject(null);  
                os.close();  
                bos.close();  
                rv = bos.toByteArray();  
            } catch (IOException e) {  
                e.printStackTrace();  
            } finally {  
                close(os);
                close(bos);
            }  
            return rv;  
        }
    
        /**
         * 反序列化列表(用于Redis整存整取)
         * @param in
         * @return
         */
        public static <T> List<T> unserializeForList(byte[] in) {  
            List<T> list = new ArrayList<T>();  
            ByteArrayInputStream bis = null;  
            ObjectInputStream is = null;  
            try {  
                if(in != null) {  
                    bis=new ByteArrayInputStream(in);  
                    is=new ObjectInputStream(bis);  
                    while (true) {  
                        T obj = (T) is.readObject();  
                        if(obj == null){  
                            break;  
                        }else{  
                            list.add(obj);  
                        }  
                    }  
                    is.close();  
                    bis.close();  
                }  
            } catch (IOException e) {  
                e.printStackTrace();
            } catch (ClassNotFoundException e) {  
                e.printStackTrace();  
            } finally {  
                close(is);  
                close(bis);  
            }  
            return list;  
        }
        
        /**
         * 关闭的数据源或目标。调用 close()方法可释放对象保存的资源(如打开文件)
         * 关闭此流并释放与此流关联的所有系统资源。如果已经关闭该流,则调用此方法无效。
         * @param closeable
         */
        public static void close(Closeable closeable) {  
            if (closeable != null) {  
                try {  
                    closeable.close();  
                } catch (Exception e) {  
                    e.printStackTrace();
                }  
            }  
        }
    }

    Module类

    package com.redis.test.module;
    
    import java.io.Serializable;
    
    public class User implements Serializable{
    
        private String name;
        
        private String password;
        
        private String address;
        
        private Integer age;
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    
        public String getPassword() {
            return password;
        }
    
        public void setPassword(String password) {
            this.password = password;
        }
    
        public String getAddress() {
            return address;
        }
    
        public void setAddress(String address) {
            this.address = address;
        }
    
        public Integer getAge() {
            return age;
        }
    
        public void setAge(Integer age) {
            this.age = age;
        }
        
        public String toString(){
            return "姓名:"+this.getName()+";"+"年龄:"+this.getAge()+";"+"地址:"+this.getAddress()+";";
        }
    }
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  • 原文地址:https://www.cnblogs.com/zyxiaohuihui/p/9069155.html
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