【 Redis中实现锁功能】---RedisTemplate

逃离我推掉我的手 2023-09-23 21:06 68阅读 0赞

### 一、Redis工具类 ###

import org.springframework.data.redis.core.RedisCallback;
    import org.springframework.data.redis.core.RedisTemplate;
    import org.springframework.data.redis.serializer.RedisSerializer;
    import org.springframework.stereotype.Service;
    
    import javax.annotation.Resource;
    import java.util.Set;
    import java.util.concurrent.TimeUnit;
    
    /**
     * redis工具类
     *
     * @author xxx
     * @date 2022/08/23
     */
    @Service
    public class RedisUtils {
        
        @Resource
        private RedisTemplate<String, Object> redisTemplate;
    
        /**
         * 添加到队列
         *
         * @param key   the key
         * @param value the value
         * @return the Long
         */
        public Long pushToList(String key, String value) {
        
            return redisTemplate.opsForList().leftPush(key, value);
        }
    
        /**
         * 字符串操作：新增或修改
         *
         * @param key   the key
         * @param value the value
         */
        public void putValue(String key, Object value) {
        
            redisTemplate.opsForValue().set(key, value);
        }
    
        /**
         * 字符串操作：新增或修改
         *
         * @param key   the key
         * @param value the value
         * @param time  有限时间，单位为秒
         */
        public void putValue(String key, Object value, long time) {
        
            redisTemplate.opsForValue().set(key, value, time, TimeUnit.SECONDS);
        }
    
        /**
         * 字符串操作：取值
         *
         * @param key the key
         * @return the Object
         */
        public Object getValue(String key) {
        
            return redisTemplate.opsForValue().get(key);
        }
    
        /**
         * 设置有效时间
         *
         * @param key  the key
         * @param time the time
         */
        public void expire(String key, long time) {
        
            redisTemplate.expire(key, time, TimeUnit.SECONDS);
        }
    
        /**
         * 删除key
         *
         * @param key the key
         */
        public void remove(String key) {
        
            redisTemplate.delete(key);
        }
    
        /**
         * 批量移除
         *
         * @param keys the keys
         */
        public void removeByKeys(String keys) {
        
            Set<String> keysSet = redisTemplate.keys(keys);
            if (keysSet != null) {
        
                redisTemplate.delete(keysSet);
            }
        }
    
        /**
         * redis主键自增
         *
         * @param key 主键值
         * @return long 类型主键
         */
        public Long incrId(final String key) {
        
            return (Long) redisTemplate.execute((RedisCallback<Long>) connection -> {
        
                RedisSerializer<String> serializer = redisTemplate.getStringSerializer();
                byte[] keys = serializer.serialize("sequence:id_" + key);
                //connection.expire(keys, 90000000);
                if (keys != null) {
        
                    return connection.incr(keys);
                } else {
        
                    return 0L;
                }
            });
        }
    
        /**
         * 新增
         * 如果为空就set值，并返回1
         * 如果存在(不为空)不进行操作，并返回0
         *
         * @param lockKey the lockKey
         * @param value   the value
         * @return the Boolean
         */
        public Boolean setIfAbsent(String lockKey, Object value) {
        
            return redisTemplate.opsForValue().setIfAbsent(lockKey, value);
        }
    
        /**
         * 新增
         * 如果为空就set值，并返回1
         * 如果存在(不为空)不进行操作，并返回0
         *
         * @param lockKey the lockKey
         * @param value   the value
         * @param time    the time
         * @return the Boolean
         */
        public Boolean setIfAbsent(String lockKey, Object value, long time) {
        
            return redisTemplate.opsForValue().setIfAbsent(lockKey, value, time, TimeUnit.SECONDS);
        }
    }

#### 二、实际应用： ####

Boolean aBoolean = redisUtils.setIfAbsent(key,value,60);
    if(aBoolean){
        
        业务逻辑.....
    }