redis学习笔记4: 在Java中操作Redis
Redis的Java客户端
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Jedis [命令和原生Redis基本相同]
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Lettuce [性能高效]
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Spring Date Redis [可以在Spring项目中使用, 简化操作]
Spring Date Redis使用方式
导入maven坐标
<!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-data-redis -->
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-data-redis</artifactId><version>3.2.4</version>
</dependency>
其他版本管理方式
<properties><redis>3.2.4</redis>
</properties><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-data-redis</artifactId><version>${redis}</version>
</dependency>
配置Redis数据源
application-dev
spring: #是spirng分级下的redis:host: localhostport: 6379password: 123456 #redis 5.0密码需要被""包裹database: 0 #一共有16个库 DB0 不同数据库的数据是完全隔离的 [在有些情况可能不被识别]
application
spring:redis:host: ${spring.redis.host}port: ${spring.redis.port}password: ${spring.redis.password}} database: ${spring.redis.database}
编写相关配置类, 创建RedisTemplate对象
@Configuration
@Slf4j
public class RedisConfiguration {@Bean //将第三方类交给IOC容器管理public RedisTemplate redisTemplate(RedisConnectionFactory redisConnectionFactory){log.info("开始创建redis模板类");RedisTemplate redisTemplate = new RedisTemplate();//设置key的序列化器, 默认为JdkSerializationRedisSerializerredisTemplate.setKeySerializer(new StringRedisSerializer());//设置redis连接工厂对象redisTemplate.setConnectionFactory(redisConnectionFactory);return redisTemplate;}
通过RedisTemplate对象操作Redis
string
public void testString(){redisTemplate.opsForValue().set("name","小明");//get keyString name = (String) redisTemplate.opsForValue().get("name");String city2 = (String) redisTemplate.opsForValue().get("city2");System.out.println(name);System.out.println(city2);//SETEX key seconds value 设置过期时间为seconds的key//SETEX code 3 1234redisTemplate.opsForValue().set("code","1234",10, TimeUnit.SECONDS); //使用枚举类写时间单位//setNX 当key不存在时创建//redis的string和java的String不是完全不同, 最后都会转化成redis字符串存储redisTemplate.opsForValue().setIfAbsent("lock",1);redisTemplate.opsForValue().setIfAbsent("lock",2);
}
hash
// @Test
public void testHash() {//hset hget hkeys hvalsHashOperations hashOperations = redisTemplate.opsForHash();//hset key filed valuehashOperations.put("100","name","tom");hashOperations.put("100","age","20");hashOperations.put("100","gender","male");//hget key fieldString name = (String) hashOperations.get("100","name");System.out.println(name);//hkeys keySet keys = hashOperations.keys("100");System.out.println(keys);//hvals keyList values = hashOperations.values("100");System.out.println(values);//hdel key fieldhashOperations.delete("100","gender");
}
set
public void testSet1(){SetOperations setOperations = redisTemplate.opsForSet();//sadd 插入新数据setOperations.add("set1","aa","bb","cc");//smembers 遍历setOperations.members("set1");//scard 元素数量Long size = setOperations.size("set1");System.out.println(size);//sinter 交集System.out.println(setOperations.intersect("set1", "set2"));//sunion 并集System.out.println(setOperations.union("set1", "set2"));//srem 删除setOperations.remove("set1","aa","bb");
}
list
public void testList(){ListOperations listOperations = redisTemplate.opsForList();//Lpush 左压栈listOperations.leftPush("mylist","aa");listOperations.leftPush("mylist","bb");listOperations.leftPush("mylist","cc");listOperations.leftPush("mylist","dd");//Llen 元素数量System.out.println(listOperations.size("mylist"));//Lrange 遍历System.out.println(listOperations.range("mylist", 0, -1));//Rpop 右弹出listOperations.rightPop("mylist");//Llen 元素数量System.out.println(listOperations.size("mylist"));
}
zset
public void testZSet(){ZSetOperations zSetOperations = redisTemplate.opsForZSet();//zadd key value score 向zset插入数据zSetOperations.add("zset1","a",19);//zrange 遍历zsetSystem.out.println(zSetOperations.range("zset1", 0, -1));//zrange key start end withScores 遍历zset并显示分数System.out.println(zSetOperations.rangeByScoreWithScores("myset1", 0, -1));//zincreby 为指定key的分数添加一个增量zSetOperations.incrementScore("zset1","c",10);//zrem 删除指定keyzSetOperations.remove("zset1","a","b");
}
通用命令操作
public void testCommon(){//keys * 查询所有keySet keys = redisTemplate.keys("*");System.out.println(keys);//exists 查询指定key是否存在Boolean name = redisTemplate.hasKey("name");//type 查询keys集合中所有数据的类型for (Object key : keys) {System.out.println(redisTemplate.type(key));}//del 根据key删除数据redisTemplate.delete("mylist");
}
其他的
在图形化界面key正常, valule显示乱码, 通过java输出是正常的
不设置序列化器, 会使用默认的序列化器, key乱码, 可以在java中查询到
