标签：etc ejs rom dde parse new cti generated val
1.redis集中式缓存
//商品详情页浏览 @RequestMapping(value = "/get",method = {RequestMethod.GET}) @ResponseBody public CommonReturnType getItem(@RequestParam(name = "id")Integer id){ ItemModel itemModel = null; // 先从本地缓存取 itemModel = (ItemModel) cacheService.getFromCommonCache("item_"+id); if(itemModel == null) { // 再从redis缓存中取 itemModel = (ItemModel) redisTemplate.opsForValue().get("item_"+id); if(itemModel == null) { // 最后从数据库取 itemModel = itemService.getItemById(id); redisTemplate.opsForValue().set("item_"+id, itemModel); redisTemplate.expire("item_"+id, 10, TimeUnit.MINUTES); } cacheService.setCommonCache("item_"+id, itemModel); } ItemVO itemVO = convertVOFromModel(itemModel); return CommonReturnType.create(itemVO); }
springboot redis存储数据会编码，去除编码直接string序列化
@Component
@EnableRedisHttpSession(maxInactiveIntervalInSeconds = 3600)
public class RedisConfig {
@Bean
public RedisTemplate<Object, Object> redisTemplate(
RedisConnectionFactory redisConnectionFactory) throws UnknownHostException {
RedisTemplate<Object, Object> template = new RedisTemplate<>();
template.setConnectionFactory(redisConnectionFactory);
// 解决key序列化方式
StringRedisSerializer stringRedisSerializer = new StringRedisSerializer();
template.setKeySerializer(stringRedisSerializer);
Jackson2JsonRedisSerializer jsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
ObjectMapper objectMapper = new ObjectMapper();
SimpleModule simpleModule = new SimpleModule();
// 时间序列化格式
simpleModule.addSerializer(DateTime.class, new JodaDateTimeJsonSerializer());
// 时间反序列化格式
simpleModule.addDeserializer(DateTime.class, new JodaDateTimeJsonDeserializer());
objectMapper.registerModule(simpleModule);
// 序列化时增加类型，方便解析成对应类型
objectMapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
jsonRedisSerializer.setObjectMapper(objectMapper);
template.setValueSerializer(jsonRedisSerializer);
return template;
}
}
/** 时间序列化 **/
public class JodaDateTimeJsonSerializer extends JsonSerializer<DateTime>{
@Override
public void serialize(DateTime value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
gen.writeString(value.toString("yyyy-MM-dd HH:mm:ss"));
}
}
/**时间反序列化**/
public class JodaDateTimeJsonDeserializer extends JsonDeserializer<DateTime> {
@Override
public DateTime deserialize(JsonParser p, DeserializationContext ctxt) throws IOException, JsonProcessingException {
String dateTime = p.readValueAs(String.class);
DateTimeFormatter format = DateTimeFormat.forPattern("yyyy-MM-dd HH:mm:ss");
return format.parseDateTime(dateTime);
}
}
缺点：redis的存或者取都需要经过网络IO达到redis Server上，并根据redis协议更新对应状态，所以相对操作本地缓存会慢些
2.本地热点缓存，使用谷歌的guava cache
@Service public class CacheServiceImpl implements CacheService { private Cache<String, Object> commonCache = null; @PostConstruct public void init() { commonCache = CacheBuilder.newBuilder() // 初始容量为10 .initialCapacity(10) // 最大容量100 .maximumSize(100) // 失效时间60秒 .expireAfterWrite(60, TimeUnit.MICROSECONDS) .build(); } @Override public void setCommonCache(String key, Object value) { commonCache.put(key, value); } @Override public Object getFromCommonCache(String key) { // TODO Auto-generated method stub return commonCache.getIfPresent(key); } }
CacheService的使用在上面getItem方法的代码中。
3.nginx缓存，shared dic共享内存字典
也是key和value类型的缓存。优势：基于nginx内存的直接缓存，并且是离用户最近的节点，但是更新机制不太好
标签：etc ejs rom dde parse new cti generated val
原文地址：https://www.cnblogs.com/t96fxi/p/12032248.html
