redis 存储对象的方法对比
问题背景:
原来项目里面全部是直接redis存储对象的json数据,需要频繁的序列化和反序列化,后来考虑更换项目中的redis存储对象为hash对象存储的,但是获取后不能方便的set get操作,很是蛋疼,怎么才能解决这个问题呢?
1.1 直接存储对象的json
存放redis的时候,直接先用fastjson 或者 jackjson或者gson把对象序列化为json数据,然后用直接存放,key表示用户id或许和openid,value则是对象的json数据
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);}优点:虽然需要序列化和反序列化,但是可以直接操作对象的方法,方便快捷
缺点:需要序列化和反序列化,并且修改单个字段,需要获取整个json,修改后,序列化保存,浪费空间,浪费时间,效率低
1.2 采用redis hash key field value 存储
key代表主键,比如用户id,或者openid,value是一个map,对应各个字段的属性和值
存放单个字段
public void hset(string key, string field, string obj) {
redistemplate.boundhashops(key).put(field,obj);
}
存放整个:
public void hsetmap(string key,map<object,object> map){
redistemplate.boundhashops(key).putall(map);
}
优点:存储方方便,节省内存空间,并且可以直接对单个字段修改,而不用获取整个对象,效率高
缺点:获取value后,是个map,不能方便的直接调用(set get)处理,需要手动map.get(filed)或者map.put(field,value)
1.3 如何解决redis hash存储对象的操作方便性问题
其实关于map和pojo的转换问题,网上给出了利用反射做的转换方法,但是加上了转换和反转,这和序列化和反序列化的问题一样了,效率问题,也不敢指直接用,纠结,思考再三,还是先维持代码不动了,以后考虑好了再说,或者广发网友有啥好解决方法,请多多指教哈!
redis存储对象的三种方式
一、 将对象序列化后保存到redis
序列化工具类实现
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;
}
}
获取jedis实例
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连接池
* */
private static void initpool(){
try {
jedispoolconfig config = new jedispoolconfig();
config.setmaxtotal(max_active);//最大连接数
config.setmaxidle(max_idle);//最大空闲连接数
config.setmaxwaitmillis(max_wait);//获取可用连接的最大等待时间
jedispool = new jedispool(config, host, port);
} catch (exception e) {
e.printstacktrace();
}
}
/*
* 获取jedis实例
* */
public synchronized static jedis getjedis() {
try {
if(jedispool == null){
initpool();
}
jedis jedis = jedispool.getresource();
jedis.auth("redis");//密码
return jedis;
} catch (exception e) {
e.printstacktrace();
return null;
}
}
}
redis操作类
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对象
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
}
测试
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、将对象用fastjson转为json字符串后存储
redis操作类
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);
}
}
测试
@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、将对象用hash数据类型存储
redis操作类
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;
}
}
测试
@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);
}
以上为个人经验,希望能给大家一个参考,也希望大家多多支持www.887551.com。