Redis最全详解（二）——客户端底层Jedis_外汇行情

Redis最全详解（二）——客户端底层Jedis

迪丽瓦拉

2024-02-19 19:21:15

0次

Redis缓存与数据库一致性

一、实时同步

对强一致要求比较高的，应采用实时同步方案，即查询缓存查询不到再从DB查询，保存到缓存；更新缓存时，先更新数据库，再将缓存的设置过期(建议不要去更新缓存内容，直接设置缓存过期)。 @Cacheable：查询时使用，注意 Long类型需转换为Sting类型，否则会抛异常 @CachePut：更新时使用，使用此注解，一定会从DB上查询数据@CacheEvict：删除时使用； @Caching：组合用法

二、异步队列

对于并发程度较高的，可采用异步队列的方式同步，可采用kafka等消息中间件处理消息生产和消费。

三、使用阿里的同步工具canal

四、采用UDF自定义函数的方式

面对mysql的API进行编程，利用触发器进行缓存同步，但UDF主要是c/c++语言实现，学习成本高。

Redis底层Jedis

Jedis淘汰了，但redis底层还是Jedis，原理是运用socket发送Resp协议的redis命令给redis服务器。

SpringBoot2.x以后使用了lettuce替代了Jedis

lettuce是高级Redis客户端，用于线程安全同步，异步和响应使用，支持集群，sentinel，管道和编辑器。

优点：

Jedis：比较全面提供了Redis的操作特性
Redission：促使使用者对Redis的关注分离，提供很多分布式相关操作服务，例如，分布式锁、分布式集合、可通过Redis支持延迟队列。
Lettuce：基于Netty框架的事件驱动的通行层，其方法调用是异步的。Lettuce的API是线程安全的，所以可以操作单个Lettuce连接来完成各种操作。

优先使用Lettuce，如果需要分布式锁，分布式集合等分布式的高级特性，添加Redisson即可。

redis.clientsjedis

spring: redis: port: 6379 password: 123456 host: 192.168.169.135 jedis: pool: max-idle: 6 #最大空闲数 max-active: 10 #最大连接数 min-idle: 2 #最小空闲数 timeout: 2000 #连接超时

JedisConfig:

package com.config.jedis; import org.slf4j.Logger; 
import org.slf4j.LoggerFactory; 
import org.springframework.beans.factory.annotation.Value; 
import org.springframework.context.annotation.Bean; 
import org.springframework.context.annotation.Configuration; 
import redis.clients.jedis.JedisPool; 
import redis.clients.jedis.JedisPoolConfig; 
/*** @ClassName JedisConfig * @Description TODO * @Author wzq * @Version 1.0 */ 
@Configuration 
public class JedisConfig { private Logger logger = LoggerFactory.getLogger(JedisConfig.class); @Value("${spring.redis.host}") private String host; @Value("${spring.redis.port}") private int port; @Value("${spring.redis.password}") private String password; @Value("${spring.redis.timeout}") private int timeout; @Value("${spring.redis.jedis.pool.max-active}") private int maxActive; @Value("${spring.redis.jedis.pool.max-idle}") private int maxIdle; @Value("${spring.redis.jedis.pool.min-idle}") private int minIdle; @Bean public JedisPool jedisPool(){ JedisPoolConfig jedisPoolConfig=new JedisPoolConfig(); jedisPoolConfig.setMaxIdle(maxIdle); jedisPoolConfig.setMinIdle(minIdle); jedisPoolConfig.setMaxTotal(maxActive);JedisPool jedisPool=new JedisPool(jedisPoolConfig,host,port,timeout,password);logger.info("JedisPool连接成功:"+host+"\t"+port); return jedisPool; } 
}

测试配置：

@SpringBootTest 
public class JedisApplicationTests { @Autowired private JedisPool jedisPool; @Test public void contextLoads() { System.out.println(jedisPool); //在连接池中得到Jedis连接 Jedisjedis=jedisPool.getResource(); jedis.set("haha","你好"); jedis.set("name","123456"); //关闭当前连接 jedis.close(); }}

工具类

package com..config.jedis; import org.springframework.beans.factory.annotation.Autowired; 
import redis.clients.jedis.Jedis; 
import redis.clients.jedis.JedisPool; /*** @ClassName JedisUtils* @Description redis客户端的命令这里都有方法 * @Author wzq * @Version 1.0 */ 
@Component 
public class JedisUtils { @Autowired private JedisPool jedisPool; /*** 获取Jedis资源 */ public Jedis getJedis(){return jedisPool.getResource(); }/*** 释放Jedis连接 */ public void close(Jedis jedis){ if(jedis!=null){ jedis.close(); } }//。。。。。。
}

redis客户端的命令这里都有方法，使用：

/*** @ClassName JedisServiceImpl * @Description TODO * @Author wzq * @Version 1.0 */ 
@Service 
@Log //日志的处理,日志不是打印
public class JedisServiceImpl { @Autowired private JedisUtils jedisUtils; /*** 测试String类型 * 根据key 查询value值 */ public String getString(String key){ Jedis jedis=jedisUtils.getJedis(); String val=null; if(!jedis.exists(key)){ val="千锋南京"; log.info(key+"在MYSQL数据库中进行查询的结果是："+val);jedis.set(key,val); log.info(key+"存入Redis中。值是："+val); }else{val=jedis.get(key); log.info(key+"是在Redis中查询的数据。值是："+val); }jedisUtils.close(jedis); //释放资源 return val;}/** * 测试 jedis 操作hash类型 * 根据用户ID查询用户信息 * 先判断Redis中是否存在， * 如果不存在，数据库中查询。并存到Redis中 * 如果存在，直接查询Redis 并返回 */ public User selectBy(String id){ String key="user:id"; //根据规则生成相同规范的key User user=new User();Jedis jedis=jedisUtils.getJedis(); if(!jedis.exists(key)){ //数据库中查询，并进行存 user.setId(id); user.setName("千锋南京JAVA"); user.setAge(20); log.info("数据库中查询的用户信息是："+user); Map map=new HashMap(); map.put("id",user.getId()); map.put("name",user.getName()); jedis.hset(key,map); log.info(key+"成功存入Redis:"+user); }else{Map map= jedis.hgetAll(key); user.setId(map.get("id"));user.setName(map.get("name")); log.info(key+"Redis中查询出来的是:"+map); }jedisUtils.close(jedis); return user; } 
}

其它的工具类，基本不用，看情况。

//Jedis工具类
package com.commons;import java.util.List;
import java.util.Map;
import java.util.Set;import org.springframework.stereotype.Component;import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;
import redis.clients.jedis.Pipeline;
import redis.clients.jedis.BinaryClient.LIST_POSITION;/**
* Redis通用工具类
* @author 【享学课堂】 James老师 qq ：1076258117  
* @author 【享学课堂】 架构技术QQ群       ：684504192 
* @author 【享学课堂】 往期视频依娜老师 ：2470523467
*/
@Component
public class JedisUtils {private JedisPool pool = null;private String ip = "192.168.169.131";private int port = 6379;private String auth = "123456";/*** 传入ip和端口号构建redis 连接*/public JedisUtils() {if (pool == null) {JedisPoolConfig config = new JedisPoolConfig();config.setMaxTotal(500);config.setMaxIdle(5);config.setMaxWaitMillis(100);config.setTestOnBorrow(true);pool = new JedisPool(config, this.ip, this.port, 100000, this.auth);}}/*** 通过key获取储存在redis中的value 并释放连* * @param key* @return 成功返回value 失败返回null*/public String get(String key) {Jedis jedis = null;String value = null;try {jedis = pool.getResource();value = jedis.get(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return value;}/*** 向redis存入key和value,并释放连接资 如果key已经存在 则覆* * @param key* @param value* @return 成功 返回OK 失败返回 0*/public String set(String key, String value) {Jedis jedis = null;try {jedis = pool.getResource();//每次操作时向pool借用个jedis对象，用完即还?return jedis.set(key, value);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();return "0";} finally {returnResource(pool, jedis);}}/*** 向redis存入序列化的key和value,并释放连接资 如果key已经存在 则覆* * @param key* @param value* @return 成功 返回OK 失败返回 0*/public String setSerializer(byte[] keyBytes, byte[] valueBytes) {Jedis jedis = null;try {jedis = pool.getResource();return jedis.set(keyBytes, valueBytes);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();return "0";} finally {returnResource(pool, jedis);}}/*** 通过序列化key获取储存在redis中的序列化value 并释放连* * @param key* @return 成功返回value 失败返回null*/public byte[] getSerializer(byte[] key) {Jedis jedis = null;byte[] value = null;try {jedis = pool.getResource();value = jedis.get(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return value;}/*** 删除指定的key,也可以传入一个包含key的数* * @param keys*            个key 也可以使 string 数组* @return 返回删除成功的个*/public Long del(String... keys) {Jedis jedis = null;try {jedis = pool.getResource();return jedis.del(keys);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();return 0L;} finally {returnResource(pool, jedis);}}/*** 通过key向指定的value值追加?* * @param key* @param str* @return 成功返回 添加后value的长 失败 返回 添加 value 的长 异常返回0L*/public Long append(String key, String str) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.append(key, str);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();return 0L;} finally {returnResource(pool, jedis);}return res;}/*** 判断key是否存在* * @param key* @return true OR false*/public Boolean exists(String key) {Jedis jedis = null;try {jedis = pool.getResource();return jedis.exists(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();return false;} finally {returnResource(pool, jedis);}}/*** 设置key value,如果key已经存在则返0,nx==> not exist* * @param key* @param value* @return 成功返回1 如果存在  发生异常 返回 0*/public Long setnx(String key, String value) {Jedis jedis = null;try {jedis = pool.getResource();return jedis.setnx(key, value);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();return 0L;} finally {returnResource(pool, jedis);}}/*** 设置key value并制定这个键值的有效* * @param key* @param value* @param seconds*            单位:* @return 成功返回OK 失败和异常返回null*/public String setex(String key, String value, int seconds) {Jedis jedis = null;String res = null;try {jedis = pool.getResource();res = jedis.setex(key, seconds, value);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key 和offset 从指定的位置始将原先value替换 下标0,offset表示从offset下标始替* 如果替换的字符串长度过小则会这样 example: value : bigsea@zto.cn str : abc 从下7始替 则结果为* RES : bigsea.abc.cn* * @param key* @param str* @param offset*            下标位置* @return 返回替换 value 的长*/public Long setrange(String key, String str, int offset) {Jedis jedis = null;try {jedis = pool.getResource();return jedis.setrange(key, offset, str);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();return 0L;} finally {returnResource(pool, jedis);}}/*** 通过批量的key获取批量的value* * @param keys*            string数组 也可以是个key* @return 成功返回value的集, 失败返回null的集 ,异常返回*/public List mget(String... keys) {Jedis jedis = null;List values = null;try {jedis = pool.getResource();values = jedis.mget(keys);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return values;}/*** 批量的设置key:value,可以 example: obj.mset(new* String[]{"key2","value1","key2","value2"})* * @param keysvalues* @return 成功返回OK 失败 异常 返回 null* */public String mset(String... keysvalues) {Jedis jedis = null;String res = null;try {jedis = pool.getResource();res = jedis.mset(keysvalues);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 删除多个字符串key 并释放连* * @param key** @return 成功返回value 失败返回null*/public boolean mdel(List keys) {Jedis jedis = null;boolean flag = false;try {jedis = pool.getResource();//从连接�用Jedis对象Pipeline pipe = jedis.pipelined();//获取jedis对象的pipeline对象for(String key:keys){pipe.del(key); //将多个key放入pipe删除指令}pipe.sync(); //执行命令，完全此时pipeline对象的远程调 flag = true;} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return flag;}/*** 批量的设置key:value,可以,如果key已经存在则会失败,操作会回 example: obj.msetnx(new* String[]{"key2","value1","key2","value2"})* * @param keysvalues* @return 成功返回1 失败返回0*/public Long msetnx(String... keysvalues) {Jedis jedis = null;Long res = 0L;try {jedis = pool.getResource();res = jedis.msetnx(keysvalues);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 设置key的?,并返回一个旧* * @param key* @param value* @return 旧? 如果key不存 则返回null*/public String getset(String key, String value) {Jedis jedis = null;String res = null;try {jedis = pool.getResource();res = jedis.getSet(key, value);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过下标 和key 获取指定下标位置 value* * @param key* @param startOffset*            始位 0  负数表示从右边开始截* @param endOffset* @return 如果没有返回null*/public String getrange(String key, int startOffset, int endOffset) {Jedis jedis = null;String res = null;try {jedis = pool.getResource();res = jedis.getrange(key, startOffset, endOffset);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key 对value进行加?+1操作,当value不是int类型时会返回错误,当key不存在是则value1* * @param key* @return 加�后的结*/public Long incr(String key) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.incr(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key给指定的value加?,如果key不存,则这是value为该* * @param key* @param integer* @return*/public Long incrBy(String key, Long integer) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.incrBy(key, integer);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 对key的�做减减操作,如果key不存,则设置key-1* * @param key* @return*/public Long decr(String key) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.decr(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 减去指定的?* * @param key* @param integer* @return*/public Long decrBy(String key, Long integer) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.decrBy(key, integer);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key获取value值的长度* * @param key* @return 失败返回null*/public Long serlen(String key) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.strlen(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key给field设置指定的?,如果key不存,则先创建* * @param key* @param field*            字段* @param value* @return 如果存在返回0 异常返回null*/public Long hset(String key, String field, String value) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.hset(key, field, value);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key给field设置指定的?,如果key不存在则先创,如果field已经存在,返回0* * @param key* @param field* @param value* @return*/public Long hsetnx(String key, String field, String value) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.hsetnx(key, field, value);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key同时设置 hash的多个field* * @param key* @param hash* @return 返回OK 异常返回null*/public String hmset(String key, Map hash) {Jedis jedis = null;String res = null;try {jedis = pool.getResource();res = jedis.hmset(key, hash);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key  field 获取指定 value* * @param key* @param field* @return 没有返回null*/public String hget(String key, String field) {Jedis jedis = null;String res = null;try {jedis = pool.getResource();res = jedis.hget(key, field);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key  fields 获取指定的value 如果没有对应的value则返回null* * @param key* @param fields*            可以 个String 也可以是 String数组* @return*/public List hmget(String key, String... fields) {Jedis jedis = null;List res = null;try {jedis = pool.getResource();res = jedis.hmget(key, fields);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key给指定的field的value加上给定的?* * @param key* @param field* @param value* @return*/public Long hincrby(String key, String field, Long value) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.hincrBy(key, field, value);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key和field判断是否有指定的value存在* * @param key* @param field* @return*/public Boolean hexists(String key, String field) {Jedis jedis = null;Boolean res = false;try {jedis = pool.getResource();res = jedis.hexists(key, field);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key返回field的数* * @param key* @return*/public Long hlen(String key) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.hlen(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}public Map hgetAll(String key) {Jedis jedis = null;Map res = null;try {jedis = pool.getResource();res = jedis.hgetAll(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key 删除指定 field* * @param key* @param fields*            可以  field 也可以是 个数* @return*/public Long hdel(String key, String... fields) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.hdel(key, fields);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}public Set zrange(String key, Long start, Long end) {Jedis jedis = null;Set res = null;try {jedis = pool.getResource();res = jedis.zrange(key, start, end);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key返回有的field* * @param key* @return*/public Set hkeys(String key) {Jedis jedis = null;Set res = null;try {jedis = pool.getResource();res = jedis.hkeys(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key返回有和key有关的value* * @param key* @return*/public List hvals(String key) {Jedis jedis = null;List res = null;try {jedis = pool.getResource();res = jedis.hvals(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key获取有的field和value* * @param key* @return*/public Map hgetall(String key) {Jedis jedis = null;Map res = null;try {jedis = pool.getResource();res = jedis.hgetAll(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key向list头部添加字符* 
* * @param key* @param strs*            可以使一个string 也可以使string数组* @return 返回list的value个数*/public Long lpush(String key, String... strs) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.lpush(key, strs);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key向list尾部添加字符* 
* * @param key* @param strs*            可以使一个string 也可以使string数组* @return 返回list的value个数*/public Long rpush(String key, String... strs) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.rpush(key, strs);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key在list指定的位置之前或者之 添加字符串元* 
* * @param key* @param where*            LIST_POSITION枚举类型* @param pivot*            list里面的value* @param value*            添加的value* @return*/public Long linsert(String key, LIST_POSITION where, String pivot, String value) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.linsert(key, where, pivot, value);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key设置list指定下标位置的value* 
* * 如果下标超过list里面value的个数则报错* 
* * @param key* @param index*            0* @param value* @return 成功返回OK*/public String lset(String key, Long index, String value) {Jedis jedis = null;String res = null;try {jedis = pool.getResource();res = jedis.lset(key, index, value);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key从对应的list中删除指定的count  value相同的元* 
* * @param key* @param count*            当count0时删除全* @param value* @return 返回被删除的个数*/public Long lrem(String key, long count, String value) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.lrem(key, count, value);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key保留list中从strat下标始到end下标结束的value* 
* * @param key* @param start* @param end* @return 成功返回OK*/public String ltrim(String key, long start, long end) {Jedis jedis = null;String res = null;try {jedis = pool.getResource();res = jedis.ltrim(key, start, end);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key从list的头部删除一个value,并返回该value* 
* * @param key* @return*/public String lpop(String key) {Jedis jedis = null;String res = null;try {jedis = pool.getResource();res = jedis.lpop(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key从list尾部删除个value,并返回该元素* 
* * @param key* @return*/public String rpop(String key) {Jedis jedis = null;String res = null;try {jedis = pool.getResource();res = jedis.rpop(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key从一个list的尾部删除一个value并添加到另一个list的头,并返回该value* 
* * 如果第一个list为空或�不存在则返回null* 
* * @param srckey* @param dstkey* @return*/public String rpoplpush(String srckey, String dstkey) {Jedis jedis = null;String res = null;try {jedis = pool.getResource();res = jedis.rpoplpush(srckey, dstkey);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key获取list中指定下标位置的value* 
* * @param key* @param index* @return 如果没有返回null*/public String lindex(String key, long index) {Jedis jedis = null;String res = null;try {jedis = pool.getResource();res = jedis.lindex(key, index);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key返回list的长* 
* * @param key* @return*/public Long llen(String key) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.llen(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key获取list指定下标位置的value* 
* * 如果start  0 end  -1 则返回全部的list中的value* 
* * @param key* @param start* @param end* @return*/public List lrange(String key, long start, long end) {Jedis jedis = null;List res = null;try {jedis = pool.getResource();res = jedis.lrange(key, start, end);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key向指定的set中添加value* 
* * @param key* @param members*            可以是一个String 也可以是个String数组* @return 添加成功的个*/public Long sadd(String key, String... members) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.sadd(key, members);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}public void expire(String key, int times) {Jedis jedis = null;try {jedis = pool.getResource();jedis.expire(key, times);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}}/*** * 通过key删除set中对应的value* 
* * @param key* @param members*            可以是一个String 也可以是个String数组* @return 删除的个*/public Long srem(String key, String... members) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.srem(key, members);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key随机删除个set中的value并返回该* 
* * @param key* @return*/public String spop(String key) {Jedis jedis = null;String res = null;try {jedis = pool.getResource();res = jedis.spop(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key获取set中的差集* 
* * 以第个set为标* 
* * @param keys*            可以使一个string 则返回set中所有的value 也可以是string数组* @return*/public Set sdiff(String... keys) {Jedis jedis = null;Set res = null;try {jedis = pool.getResource();res = jedis.sdiff(keys);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key获取set中的差集并存入到另一个key* 
* * 以第个set为标* 
* * @param dstkey*            差集存入的key* @param keys*            可以使一个string 则返回set中所有的value 也可以是string数组* @return*/public Long sdiffstore(String dstkey, String... keys) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.sdiffstore(dstkey, keys);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key获取指定set中的交集* 
* * @param keys*            可以使一个string 也可以是个string数组* @return*/public Set sinter(String... keys) {Jedis jedis = null;Set res = null;try {jedis = pool.getResource();res = jedis.sinter(keys);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key获取指定set中的交集 并将结果存入新的set* 
* * @param dstkey* @param keys*            可以使一个string 也可以是个string数组* @return*/public Long sinterstore(String dstkey, String... keys) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.sinterstore(dstkey, keys);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key返回有set的并* 
* * @param keys*            可以使一个string 也可以是个string数组* @return*/public Set sunion(String... keys) {Jedis jedis = null;Set res = null;try {jedis = pool.getResource();res = jedis.sunion(keys);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key返回有set的并,并存入到新的set* 
* * @param dstkey* @param keys*            可以使一个string 也可以是个string数组* @return*/public Long sunionstore(String dstkey, String... keys) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.sunionstore(dstkey, keys);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key将set中的value移除并添加到第二个set* 
* * @param srckey*            要移除的* @param dstkey*            添加* @param member*            set中的value* @return*/public Long smove(String srckey, String dstkey, String member) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.smove(srckey, dstkey, member);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key获取set中value的个* 
* * @param key* @return*/public Long scard(String key) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.scard(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key判断value是否是set中的元素* 
* * @param key* @param member* @return*/public Boolean sismember(String key, String member) {Jedis jedis = null;Boolean res = null;try {jedis = pool.getResource();res = jedis.sismember(key, member);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key获取set中随机的value,不删除元* 
* * @param key* @return*/public String srandmember(String key) {Jedis jedis = null;String res = null;try {jedis = pool.getResource();res = jedis.srandmember(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** * 通过key获取set中所有的value* 
* * @param key* @return*/public Set smembers(String key) {Jedis jedis = null;Set res = null;try {jedis = pool.getResource();res = jedis.smembers(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key向zset中添加value,score,其中score就是用来排序 如果该value已经存在则根据score更新元素* * @param key* @param scoreMembers* @return*/public Long zadd(String key, Map scoreMembers) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.zadd(key, scoreMembers);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key向zset中添加value,score,其中score就是用来排序 如果该value已经存在则根据score更新元素* * @param key* @param score* @param member* @return*/public Long zadd(String key, double score, String member) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.zadd(key, score, member);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key删除在zset中指定的value* * @param key* @param members*            可以使一个string 也可以是个string数组* @return*/public Long zrem(String key, String... members) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.zrem(key, members);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key增加该zset中value的score的?* * @param key* @param score* @param member* @return*/public Double zincrby(String key, double score, String member) {Jedis jedis = null;Double res = null;try {jedis = pool.getResource();res = jedis.zincrby(key, score, member);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}public long hincrBy(String key, String field, long value) {Jedis jedis = null;long res = 0l;try {jedis = pool.getResource();res = jedis.hincrBy(key, field, value);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key返回zset中value的排 下标从小到大排序* * @param key* @param member* @return*/public Long zrank(String key, String member) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.zrank(key, member);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key返回zset中value的排 下标从大到小排序* * @param key* @param member* @return*/public Long zrevrank(String key, String member) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.zrevrank(key, member);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key将获取score从start到end中zset的value socre从大到小排序 当start0 end-1时返回全* * @param key* @param start* @param end* @return*/public Set zrevrange(String key, long start, long end) {Jedis jedis = null;Set res = null;try {jedis = pool.getResource();res = jedis.zrevrange(key, start, end);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key返回指定score内zset中的value* * @param key* @param max* @param min* @return*/public Set zrangebyscore(String key, String max, String min) {Jedis jedis = null;Set res = null;try {jedis = pool.getResource();res = jedis.zrevrangeByScore(key, max, min);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key返回指定score内zset中的value* * @param key* @param max* @param min* @return*/public Set zrangeByScore(String key, double max, double min) {Jedis jedis = null;Set res = null;try {jedis = pool.getResource();res = jedis.zrevrangeByScore(key, max, min);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 返回指定区间内zset中value的数* * @param key* @param min* @param max* @return*/public Long zcount(String key, String min, String max) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.zcount(key, min, max);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key返回zset中的value个数* * @param key* @return*/public Long zcard(String key) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.zcard(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key获取zset中value的score* * @param key* @param member* @return*/public Double zscore(String key, String member) {Jedis jedis = null;Double res = null;try {jedis = pool.getResource();res = jedis.zscore(key, member);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key删除给定区间内的元素* * @param key* @param start* @param end* @return*/public Long zremrangeByRank(String key, long start, long end) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.zremrangeByRank(key, start, end);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key删除指定score内的元素* * @param key* @param start* @param end* @return*/public Long zremrangeByScore(String key, double start, double end) {Jedis jedis = null;Long res = null;try {jedis = pool.getResource();res = jedis.zremrangeByScore(key, start, end);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 返回满足pattern表达式的有key keys(*) 返回有的key* * @param pattern* @return*/public Set keys(String pattern) {Jedis jedis = null;Set res = null;try {jedis = pool.getResource();res = jedis.keys(pattern);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 通过key判断值得类型* * @param key* @return*/public String type(String key) {Jedis jedis = null;String res = null;try {jedis = pool.getResource();res = jedis.type(key);} catch (Exception e) {pool.returnBrokenResource(jedis);e.printStackTrace();} finally {returnResource(pool, jedis);}return res;}/*** 返还到连接池* * @param pool* @param redis*/public static void returnResource(JedisPool pool, Jedis jedis) {if (jedis != null) {pool.returnResource(jedis);}}
}

Redis模糊查询

方法一：keys 命令

// 通配符*
Set keys = redisTemplate.keys("*message:*");
Iterator iterator = list.iterator();
List msgLikes=new ArrayList<>(256);
while (iterator.hasNext()){//遍历操作；
}

模糊查询：返回所有符合key的集合；

命令优点是简单，初学者拿来即用。(但通常运维大神会在redis服务端禁用该命令)，缺点是可能会直接导致redis服务宕机。由于redis服务是单线程工作，每一条到达的指令都是串行执行，而Keys 命令会全量遍历缓存中的所有key，直到结束，如果redis中的key数量太多、所需要的时间就很长，此刻请求redis服务的其它指令都将被阻塞，后台服务可能会因为超时而报错；

方法二：scan命令

SCAN cursor [MATCH pattern] [COUNT count] [TYPE type]

cursor：游标；默认为0；
pattern: 需要进行模糊查询的字符串；与keys的pattern相同；可省略；
count:返回多少条符合的key; 可省略
Type: 模糊查询返回的key的类型；可为String,Hash,List,Set,Zset; 可省略

public class RedisUtils {public static Logger log= LoggerFactory.getLogger(RedisUtils.class);/*** 获取 指定格式的所有key* 迭代执行 SCAN 0 MATCH {pattern} COUNT 10000** @param redisTemplate redisTemplate* @param pattern       匹配规则，带通配符*pattern** @return 指定格式的所有key*/public static List scanKeys(RedisTemplate redisTemplate, String pattern) {//SCAN 0 MATCH {pattern} COUNT 10000return (List) redisTemplate.execute(connection -> {//scan 迭代遍历键，返回的结果可能会有重复，需要客户端去重复Set redisKeys = new HashSet<>();//lettuce 原生apiRedisAsyncCommands conn = (RedisAsyncCommands) connection.getNativeConnection();//游标ScanCursor curs = ScanCursor.INITIAL;try {//采用 SCAN 命令，迭代遍历所有keywhile (!curs.isFinished()) {long count = 10000L;ScanArgs args = ScanArgs.Builder.matches(pattern).limit(count);log.info("SCAN {} MATCH {} COUNT {}", curs.getCursor(), pattern, count);RedisFuture> future = conn.scan(curs, args);KeyScanCursor keyCurs = future.get();List ks = keyCurs.getKeys();Set set = ks.stream().map(bytes -> new String(bytes, StandardCharsets.UTF_8)).collect(Collectors.toSet());log.info("return size:{}", set.size());redisKeys.addAll(set);curs = keyCurs;}} catch (InterruptedException | ExecutionException e) {throw new RuntimeException(e);}return new ArrayList<>(redisKeys);}, true);}}

核心是采用 lettuce 原生api。
io.lettuce.core.api.async.RedisAsyncCommands#scan()

    /*** Incrementally iterate the keys space.** @param scanCursor cursor to resume from a previous scan, must not be {@literal null}* @param scanArgs scan arguments* @return KeyScanCursor<K> scan cursor.*/RedisFuture> scan(ScanCursor scanCursor, ScanArgs scanArgs);

io.lettuce.core.ScanCursor 是迭代遍历的游标

io.lettuce.core.ScanArgs 是Scan的参数，包括count和pattern字符串。

io.lettuce.core.KeyScanCursor 是每次迭代后的返回数据，包含下次迭代的游标和此次迭代返回的keys列表。

原生api可以获取到每次迭代后下次迭代的游标，便于采用轮询的方式实现真正的迭代遍历。

采用scan 迭代遍历键，返回的结果可能会有重复，需要客户端去重复。代码中用 Set，存储每次迭代的key列表，可实现去重。

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