Mybatis：整合Redis缓存

￡神魔★判官ぃ 2024-03-22 12:15 98阅读 0赞

### Mybatis：整合Redis缓存 ###

#### 配置 ####

import lombok.extern.slf4j.Slf4j;
    import org.apache.ibatis.cache.Cache;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.beans.factory.annotation.Qualifier;
    import org.springframework.data.redis.core.RedisCallback;
    import org.springframework.data.redis.core.RedisTemplate;
    import org.springframework.data.redis.connection.RedisServerCommands;
    import org.springframework.util.CollectionUtils;
    
    import java.util.concurrent.locks.ReadWriteLock;
    import java.util.concurrent.locks.ReentrantReadWriteLock;
    
    @Slf4j
    public class MybatisRedisCache implements Cache {
        
    
    
        // 读写锁
        private final ReadWriteLock readWriteLock = new ReentrantReadWriteLock(true);
    
        //这里使用了redis缓存，使用springboot自动注入
        @Autowired
        @Qualifier("redisTemplate3")
        private RedisTemplate<String, Object> redisTemplate;
    
        private String id;
    
        public MybatisRedisCache(final String id) {
        
            if (id == null) {
        
                throw new IllegalArgumentException("Cache instances require an ID");
            }
            this.id = id;
        }
    
        @Override
        public String getId() {
        
            return this.id;
        }
    
        @Override
        public void putObject(Object key, Object value) {
        
            if (redisTemplate == null) {
        
                //由于启动期间注入失败，只能运行期间注入，这段代码可以删除
                redisTemplate = (RedisTemplate<String, Object>) AppCtxUtils.getBean("redisTemplate3");
            }
            if (value != null) {
        
                redisTemplate.opsForValue().set(key.toString(), value);
            }
        }
    
        @Override
        public Object getObject(Object key) {
        
            try {
        
                if (key != null) {
        
                    return redisTemplate.opsForValue().get(key.toString());
                }
            } catch (Exception e) {
        
                log.error("缓存数据不存在 ");
            }
            return null;
        }
    
        @Override
        public Object removeObject(Object key) {
        
            if (key != null) {
        
                redisTemplate.delete(key.toString());
            }
            return null;
        }
    
        @Override
        public void clear() {
        
            log.debug("清空缓存");
            if (redisTemplate == null) {
        
                redisTemplate = (RedisTemplate<String, Object>) AppCtxUtils.getBean("redisTemplate3");
            }
            Set<String> keys = redisTemplate.keys("*:" + this.id + "*");
            if (!CollectionUtils.isEmpty(keys)) {
        
                redisTemplate.delete(keys);
            }
        }
    
        @Override
        public int getSize() {
        
            Long size = redisTemplate.execute((RedisCallback<Long>) RedisServerCommands::dbSize);
            return size.intValue();
        }
    
        @Override
        public ReadWriteLock getReadWriteLock() {
        
            return this.readWriteLock;
        }
    }

#### 工具类 ####

import org.springframework.beans.BeansException;
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.ApplicationContextAware;
    import org.springframework.stereotype.Component;
    
    @Component
    public class AppCtxUtils implements ApplicationContextAware {
        
    
        private static ApplicationContext appCtx;
    
        @Override
        public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        
            appCtx = applicationContext;
        }
    
        public static <T> T getBean(Class<T> clazz) {
        
            return appCtx.getBean(clazz);
        }
    
        public static <T> T getBean(String beanName) {
        
            return (T) appCtx.getBean(beanName);
        }
    }

#### 使用 ####

import org.apache.ibatis.annotations.CacheNamespace;
    
    @CacheNamespace(implementation= MybatisRedisCache.class,eviction= MybatisRedisCache.class)
    public interface DemoMapper {
        
    }