redis 存儲對象的方法對比分析

redis 存儲對象的方法對比

問題背景:

原來項目裡面全部是直接redis存儲對象的json數據,需要頻繁的序列化和反序列化,後來考慮更換項目中的redis存儲對象為hash對象存儲的,但是獲取後不能方便的set get操作,很是蛋疼,怎麼才能解決這個問題呢?

1.1 直接存儲對象的json

存放redis的時候,直接先用fastJson 或者 jackJson或者Gson把對象序列化為json數據,然後用直接存放,key表示用戶id或許和openid,value則是對象的json數據

public String get(String key) {
Object value = redisTemplate.boundValueOps(key).get();
return (String) value;
}
public void set(String key, String json) {
if (json == null) {
return;
}
redisTemplate.boundValueOps(key).set(json);
}

優點:雖然需要序列化和反序列化,但是可以直接操作對象的方法,方便快捷

缺點:需要序列化和反序列化,並且修改單個字段,需要獲取整個json,修改後,序列化保存,浪費空間,浪費時間,效率低

1.2 采用redis hash key field value 存儲

key代表主鍵,比如用戶id,或者openId,value是一個map,對應各個字段的屬性和值

存放單個字段

public void hset(String key, String field, String obj) {
redisTemplate.boundHashOps(key).put(field,obj);
}

存放整個:

public void hSetMap(String key,Map<Object,Object> map){
redisTemplate.boundHashOps(key).putAll(map);
}

優點:存儲方方便,節省內存空間,並且可以直接對單個字段修改,而不用獲取整個對象,效率高

缺點:獲取value後,是個map,不能方便的直接調用(set get)處理,需要手動map.get(filed)或者map.put(field,value)

1.3 如何解決redis hash存儲對象的操作方便性問題

其實關於map和pojo的轉換問題,網上給出瞭利用反射做的轉換方法,但是加上瞭轉換和反轉,這和序列化和反序列化的問題一樣瞭,效率問題,也不敢指直接用,糾結,思考再三,還是先維持代碼不動瞭,以後考慮好瞭再說,或者廣發網友有啥好解決方法,請多多指教哈!

Redis存儲對象的三種方式

一、 將對象序列化後保存到Redis

序列化工具類實現

public class SerializeUtil {
    /*
     * 序列化
     * */
    public static byte[] serizlize(Object object){
        ObjectOutputStream oos = null;
        ByteArrayOutputStream baos = null;
        try {
            baos = new ByteArrayOutputStream();
            oos = new ObjectOutputStream(baos);
            oos.writeObject(object);
            byte[] bytes = baos.toByteArray();
            return bytes;
        } catch (Exception e) {
            e.printStackTrace();
        }finally {
            try {
                if(baos != null){
                    baos.close();
                }
                if (oos != null) {
                    oos.close();
                }
            } catch (Exception e2) {
                e2.printStackTrace();
            }
        }
        return null;
    }
    /*
     * 反序列化
     * */
    public static Object deserialize(byte[] bytes){
        ByteArrayInputStream bais = null;
        ObjectInputStream ois = null; 
        try{
            bais = new ByteArrayInputStream(bytes);
            ois = new ObjectInputStream(bais);
            return ois.readObject();
        }catch(Exception e){
            e.printStackTrace();
        }finally {
            try {
 
            } catch (Exception e2) {
                e2.printStackTrace();
            }
        }
        return null;
    }
}

獲取jedis實例

public class RedisConnection {
    private static String HOST = "127.0.0.1";
    private static int PORT = 6379;
    private static int MAX_ACTIVE = 1024;
    private static int MAX_IDLE = 200;
    private static int MAX_WAIT = 10000;
 
    private static JedisPool jedisPool = null;
 
    /*
     * 初始化redis連接池
     * */
    private static void initPool(){
        try {
            JedisPoolConfig config = new JedisPoolConfig();
            config.setMaxTotal(MAX_ACTIVE);//最大連接數
            config.setMaxIdle(MAX_IDLE);//最大空閑連接數
            config.setMaxWaitMillis(MAX_WAIT);//獲取可用連接的最大等待時間
 
            jedisPool = new JedisPool(config, HOST, PORT);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
 
    /*
     * 獲取jedis實例
     * */
    public synchronized static Jedis getJedis() {
        try {
            if(jedisPool == null){
                initPool();
            }
            Jedis jedis = jedisPool.getResource();
            jedis.auth("redis");//密碼
            return jedis;
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }
}

redis操作類

public class RedisOps {
    public static void set(String key,String value){
        Jedis jedis = RedisConnection.getJedis();
        jedis.set(key, value);
        jedis.close();
    }
    public static String get(String key){
        Jedis jedis = RedisConnection.getJedis();
        String value = jedis.get(key);
        jedis.close();
        return value;
    }
    public static void setObject(String key,Object object){
        Jedis jedis = RedisConnection.getJedis();
        jedis.set(key.getBytes(), SerializeUtil.serizlize(object));
        jedis.close();
    }
    public static Object getObject(String key){
        Jedis jedis = RedisConnection.getJedis();
        byte[] bytes = jedis.get(key.getBytes());
        jedis.close();
        return SerializeUtil.deserialize(bytes);
    }
}

User對象

public class User implements Serializable{
    private static final long serialVersionUID = -3210884885630038713L;
    private int id;
    private String name;
    public User(){
 
    }
    public User(int id,String name){
        this.id = id;
        this.name = name;
    }
    //setter和getter方法
}

測試

public class RedisTest {
 
    @Test
    public void testString(){
        RedisOps.set("user:1", "sisu");
        String user = RedisOps.get("user:1");
        Assert.assertEquals("sisu", user);
    }
 
    @Test
    public void testObject(){
        RedisOps.setObject("user:2",new User(2,"lumia"));
        User user = (User)RedisOps.getObject("user:2");
        Assert.assertEquals("lumia", user.getName());
    } 
}

二、將對象用FastJSON轉為JSON字符串後存儲

redis操作類

public class RedisOps {
    public static void setJsonString(String key,Object object){
        Jedis jedis = RedisConnection.getJedis();
        jedis.set(key, JSON.toJSONString(object));
        jedis.close();
    }
    public static Object getJsonObject(String key,Class clazz){
        Jedis jedis = RedisConnection.getJedis();
        String value = jedis.get(key);
        jedis.close();
        return JSON.parseObject(value,clazz);
    }
}

測試

 @Test
    public void testObject2(){
        RedisOps.setJsonString("user:3", new User(3,"xiaoming"));
        User user = (User)RedisOps.getJsonObject("user:3",User.class);
        Assert.assertEquals("xiaoming", user.getName());
    }

三、將對象用Hash數據類型存儲

redis操作類

public class RedisOps {
    public static void hSet(String key,String value){
        Jedis jedis = RedisConnection.getJedis();
        jedis.hSet(key, value);
        jedis.close();
    }
    public static String hGet(String key){
        Jedis jedis = RedisConnection.getJedis();
        String value = jedis.hGet(key);
        jedis.close();
        return value;
    }
}

測試

 @Test
    public void testObject3(){
     //存
        RedisOps.hSet("user:3","id","3");
        RedisOps.hSet("user:3","name","xiaoming");
        
        //取
        String id =  RedisOps..hGet("user:3","id");
        String name = RedisOps.hGet("user:3","name");
        Assert.assertEquals("3", id);
        Assert.assertEquals("xiaoming", name);        
    }

以上為個人經驗,希望能給大傢一個參考,也希望大傢多多支持WalkonNet。

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