官方建議在service使用緩存,可是你也能夠直接在mapper層緩存,這裏的二級緩存就是直接在Mapper層進行緩存操做redis
mybatis-plus: configuration: cache-enabled: true
public class MybatisRedisCache implements Cache { // 讀寫鎖 private final ReadWriteLock readWriteLock = new ReentrantReadWriteLock(true); //這裏使用了redis緩存,使用springboot自動注入 @Autowired 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) { //因爲啓動期間注入失敗,只能運行期間注入,這段代碼能夠刪除 redisTemplate = (RedisTemplate<String, Object>) ApplicationContextRegister.getApplicationContext().getBean("RedisTemplate"); } 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("緩存出錯 "); } return null; } @Override public Object removeObject(Object key) { if (key != null) { redisTemplate.delete(key.toString()); } return null; } @Override public void clear() { log.debug("清空緩存"); if (redisTemplate == null) { redisTemplate = (RedisTemplate<String, Object>) ApplicationContextRegister.getApplicationContext().getBean("functionDomainRedisTemplate"); } 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; } }
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="com.zsy.mapper.CarouselMapper"> <cache-ref namespace="com.zsy.mapper.CarouselMapper"/> </mapper>
@Repository @CacheNamespace(implementation=MybatisRedisCache.class,eviction=MybatisRedisCache.class) public interface CarouselMapper extends BaseMapper<Carousel> {}