<!-- spring boot redis緩存引入 -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
<!-- 緩存連接池-->
<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-pool2</artifactId>
</dependency>
<!-- redis 存儲 json序列化 -->
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
</dependency>
<dependency>
    <groupId>com.fasterxml.jackson.datatype</groupId>
    <artifactId>jackson-datatype-jsr310</artifactId>
</dependency>

@SpringBootTest
@RunWith(SpringRunner.class)
public class RedisTemplateTests {
    @Resource
    private RedisTemplate redisTemplate;
    @Resource
    private DictMapper dictMapper;
    @Test
    public void saveDict(){
        Dict dict = dictMapper.selectById(1);
        //向數(shù)據(jù)庫中存儲string類型的鍵值對, 過期時間5分鐘
        redisTemplate.opsForValue().set("dict", dict, 5, TimeUnit.MINUTES);
    }
}

@Configuration
public class RedisConfig {
    @Bean
    public RedisTemplate<String, Object> redisTemplate(LettuceConnectionFactory redisConnectionFactory) {
        RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();
        redisTemplate.setConnectionFactory(redisConnectionFactory);
        //首先解決key的序列化方式
        StringRedisSerializer stringRedisSerializer = new StringRedisSerializer();
        redisTemplate.setKeySerializer(stringRedisSerializer);
        //解決value的序列化方式
        Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer<>(Object.class);
        //序列化時將類的數(shù)據(jù)類型存入json，以便反序列化的時候轉(zhuǎn)換成正確的類型
        ObjectMapper objectMapper = new ObjectMapper();
        //objectMapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
        objectMapper.activateDefaultTyping(LaissezFaireSubTypeValidator.instance, ObjectMapper.DefaultTyping.NON_FINAL);
        // 解決jackson2無法反序列化LocalDateTime的問題
        objectMapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
        objectMapper.registerModule(new JavaTimeModule());
        jackson2JsonRedisSerializer.setObjectMapper(objectMapper);
        redisTemplate.setValueSerializer(jackson2JsonRedisSerializer);
        return redisTemplate;
    }
}

@Test
public void getDict(){
    Dict dict = (Dict)redisTemplate.opsForValue().get("dict");
    System.out.println(dict);
}

@Resource
private RedisTemplate redisTemplate;
@Override
public List<Dict> listByParentId(Long parentId) {
    //先查詢redis中是否存在數(shù)據(jù)列表
    List<Dict> dictList = null;
    try {
        dictList = (List<Dict>)redisTemplate.opsForValue().get("srb:core:dictList:" + parentId);
        if(dictList != null){
            log.info("從redis中取值");
            return dictList;
        }
    } catch (Exception e) {
        log.error("redis服務(wù)器異常：" + ExceptionUtils.getStackTrace(e));//此處不拋出異常，繼續(xù)執(zhí)行后面的代碼
    }
    log.info("從數(shù)據(jù)庫中取值");
    dictList = baseMapper.selectList(new QueryWrapper<Dict>().eq("parent_id", parentId));
    dictList.forEach(dict -> {
        //如果有子節(jié)點，則是非葉子節(jié)點
        boolean hasChildren = this.hasChildren(dict.getId());
        dict.setHasChildren(hasChildren);
    });
    //將數(shù)據(jù)存入redis
    try {
        redisTemplate.opsForValue().set("srb:core:dictList:" + parentId, dictList, 5, TimeUnit.MINUTES);
        log.info("數(shù)據(jù)存入redis");
    } catch (Exception e) {
        log.error("redis服務(wù)器異常：" + ExceptionUtils.getStackTrace(e));//此處不拋出異常，繼續(xù)執(zhí)行后面的代碼
    }
    return dictList;
}