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。